local variable before assignment python

Fix "local variable referenced before assignment" in Python

Introduction

If you're a Python developer, you've probably come across a variety of errors, like the "local variable referenced before assignment" error. This error can be a bit puzzling, especially for beginners and when it involves local/global variables.

Today, we'll explain this error, understand why it occurs, and see how you can fix it.

The "local variable referenced before assignment" Error

The "local variable referenced before assignment" error in Python is a common error that occurs when a local variable is referenced before it has been assigned a value. This error is a type of UnboundLocalError , which is raised when a local variable is referenced before it has been assigned in the local scope.

Here's a simple example:

Running this code will throw the "local variable 'x' referenced before assignment" error. This is because the variable x is referenced in the print(x) statement before it is assigned a value in the local scope of the foo function.

Even more confusing is when it involves global variables. For example, the following code also produces the error:

But wait, why does this also produce the error? Isn't x assigned before it's used in the say_hello function? The problem here is that x is a global variable when assigned "Hello ". However, in the say_hello function, it's a different local variable, which has not yet been assigned.

We'll see later in this Byte how you can fix these cases as well.

Fixing the Error: Initialization

One way to fix this error is to initialize the variable before using it. This ensures that the variable exists in the local scope before it is referenced.

Let's correct the error from our first example:

In this revised code, we initialize x with a value of 1 before printing it. Now, when you run the function, it will print 1 without any errors.

Fixing the Error: Global Keyword

Another way to fix this error, depending on your specific scenario, is by using the global keyword. This is especially useful when you want to use a global variable inside a function.

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Here's how:

In this snippet, we declare x as a global variable inside the function foo . This tells Python to look for x in the global scope, not the local one . Now, when you run the function, it will increment the global x by 1 and print 1 .

Similar Error: NameError

An error that's similar to the "local variable referenced before assignment" error is the NameError . This is raised when you try to use a variable or a function name that has not been defined yet.

Running this code will result in a NameError :

In this case, we're trying to print the value of y , but y has not been defined anywhere in the code. Hence, Python raises a NameError . This is similar in that we are trying to use an uninitialized/undefined variable, but the main difference is that we didn't try to initialize y anywhere else in our code.

Variable Scope in Python

Understanding the concept of variable scope can help avoid many common errors in Python, including the main error of interest in this Byte. But what exactly is variable scope?

In Python, variables have two types of scope - global and local. A variable declared inside a function is known as a local variable, while a variable declared outside a function is a global variable.

Consider this example:

In this code, x is a global variable, and y is a local variable. x can be accessed anywhere in the code, but y can only be accessed within my_function . Confusion surrounding this is one of the most common causes for the "variable referenced before assignment" error.

In this Byte, we've taken a look at the "local variable referenced before assignment" error and another similar error, NameError . We also delved into the concept of variable scope in Python, which is an important concept to understand to avoid these errors. If you're seeing one of these errors, check the scope of your variables and make sure they're being assigned before they're being used.

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How to Fix Local Variable Referenced Before Assignment Error in Python

Table of Contents

Fixing local variable referenced before assignment error.

In Python , when you try to reference a variable that hasn't yet been given a value (assigned), it will throw an error.

That error will look like this:

In this post, we'll see examples of what causes this and how to fix it.

Let's begin by looking at an example of this error:

If you run this code, you'll get

The issue is that in this line:

We are defining a local variable called value and then trying to use it before it has been assigned a value, instead of using the variable that we defined in the first line.

If we want to refer the variable that was defined in the first line, we can make use of the global keyword.

The global keyword is used to refer to a variable that is defined outside of a function.

Let's look at how using global can fix our issue here:

Global variables have global scope, so you can referenced them anywhere in your code, thus avoiding the error.

If you run this code, you'll get this output:

In this post, we learned at how to avoid the local variable referenced before assignment error in Python.

The error stems from trying to refer to a variable without an assigned value, so either make use of a global variable using the global keyword, or assign the variable a value before using it.

Thanks for reading!

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[SOLVED] Local Variable Referenced Before Assignment

Python treats variables referenced only inside a function as global variables. Any variable assigned to a function’s body is assumed to be a local variable unless explicitly declared as global.

Why Does This Error Occur?

Unboundlocalerror: local variable referenced before assignment occurs when a variable is used before its created. Python does not have the concept of variable declarations. Hence it searches for the variable whenever used. When not found, it throws the error.

Before we hop into the solutions, let’s have a look at what is the global and local variables.

Local Variable Declarations vs. Global Variable Declarations

Local Variable Referenced Before Assignment Error with Explanation

Try these examples yourself using our Online Compiler.

Let’s look at the following function:

Explanation

The variable myVar has been assigned a value twice. Once before the declaration of myFunction and within myFunction itself.

Using Global Variables

Passing the variable as global allows the function to recognize the variable outside the function.

Create Functions that Take in Parameters

Instead of initializing myVar as a global or local variable, it can be passed to the function as a parameter. This removes the need to create a variable in memory.

UnboundLocalError: local variable ‘DISTRO_NAME’

This error may occur when trying to launch the Anaconda Navigator in Linux Systems.

Upon launching Anaconda Navigator, the opening screen freezes and doesn’t proceed to load.

Try and update your Anaconda Navigator with the following command.

If solution one doesn’t work, you have to edit a file located at

After finding and opening the Python file, make the following changes:

In the function on line 159, simply add the line:

DISTRO_NAME = None

Save the file and re-launch Anaconda Navigator.

DJANGO – Local Variable Referenced Before Assignment [Form]

The program takes information from a form filled out by a user. Accordingly, an email is sent using the information.

Upon running you get the following error:

We have created a class myForm that creates instances of Django forms. It extracts the user’s name, email, and message to be sent.

A function GetContact is created to use the information from the Django form and produce an email. It takes one request parameter. Prior to sending the email, the function verifies the validity of the form. Upon True , .get() function is passed to fetch the name, email, and message. Finally, the email sent via the send_mail function

Why does the error occur?

We are initializing form under the if request.method == “POST” condition statement. Using the GET request, our variable form doesn’t get defined.

Local variable Referenced before assignment but it is global

This is a common error that happens when we don’t provide a value to a variable and reference it. This can happen with local variables. Global variables can’t be assigned.

This error message is raised when a variable is referenced before it has been assigned a value within the local scope of a function, even though it is a global variable.

Here’s an example to help illustrate the problem:

In this example, x is a global variable that is defined outside of the function my_func(). However, when we try to print the value of x inside the function, we get a UnboundLocalError with the message “local variable ‘x’ referenced before assignment”.

This is because the += operator implicitly creates a local variable within the function’s scope, which shadows the global variable of the same name. Since we’re trying to access the value of x before it’s been assigned a value within the local scope, the interpreter raises an error.

To fix this, you can use the global keyword to explicitly refer to the global variable within the function’s scope:

However, in the above example, the global keyword tells Python that we want to modify the value of the global variable x, rather than creating a new local variable. This allows us to access and modify the global variable within the function’s scope, without causing any errors.

Local variable ‘version’ referenced before assignment ubuntu-drivers

This error occurs with Ubuntu version drivers. To solve this error, you can re-specify the version information and give a split as 2 –

Here, p_name means package name.

With the help of the threading module, you can avoid using global variables in multi-threading. Make sure you lock and release your threads correctly to avoid the race condition.

When a variable that is created locally is called before assigning, it results in Unbound Local Error in Python. The interpreter can’t track the variable.

Therefore, we have examined the local variable referenced before the assignment Exception in Python. The differences between a local and global variable declaration have been explained, and multiple solutions regarding the issue have been provided.

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Local variable referenced before assignment in Python

Last updated: Apr 8, 2024 Reading time · 4 min

# Local variable referenced before assignment in Python

The Python "UnboundLocalError: Local variable referenced before assignment" occurs when we reference a local variable before assigning a value to it in a function.

To solve the error, mark the variable as global in the function definition, e.g. global my_var .

Here is an example of how the error occurs.

We assign a value to the name variable in the function.

# Mark the variable as global to solve the error

To solve the error, mark the variable as global in your function definition.

If a variable is assigned a value in a function's body, it is a local variable unless explicitly declared as global .

# Local variables shadow global ones with the same name

You could reference the global name variable from inside the function but if you assign a value to the variable in the function's body, the local variable shadows the global one.

Accessing the name variable in the function is perfectly fine.

On the other hand, variables declared in a function cannot be accessed from the global scope.

The name variable is declared in the function, so trying to access it from outside causes an error.

Make sure you don't try to access the variable before using the global keyword, otherwise, you'd get the SyntaxError: name 'X' is used prior to global declaration error.

# Returning a value from the function instead

An alternative solution to using the global keyword is to return a value from the function and use the value to reassign the global variable.

We simply return the value that we eventually use to assign to the name global variable.

# Passing the global variable as an argument to the function

You should also consider passing the global variable as an argument to the function.

We passed the name global variable as an argument to the function.

If we assign a value to a variable in a function, the variable is assumed to be local unless explicitly declared as global .

# Assigning a value to a local variable from an outer scope

If you have a nested function and are trying to assign a value to the local variables from the outer function, use the nonlocal keyword.

The nonlocal keyword allows us to work with the local variables of enclosing functions.

Had we not used the nonlocal statement, the call to the print() function would have returned an empty string.

Printing the message variable on the last line of the function shows an empty string because the inner() function has its own scope.

Changing the value of the variable in the inner scope is not possible unless we use the nonlocal keyword.

Instead, the message variable in the inner function simply shadows the variable with the same name from the outer scope.

# Discussion

As shown in this section of the documentation, when you assign a value to a variable inside a function, the variable:

• Becomes local to the scope.
• Shadows any variables from the outer scope that have the same name.

The last line in the example function assigns a value to the name variable, marking it as a local variable and shadowing the name variable from the outer scope.

At the time the print(name) line runs, the name variable is not yet initialized, which causes the error.

The most intuitive way to solve the error is to use the global keyword.

The global keyword is used to indicate to Python that we are actually modifying the value of the name variable from the outer scope.

• If a variable is only referenced inside a function, it is implicitly global.
• If a variable is assigned a value inside a function's body, it is assumed to be local, unless explicitly marked as global .

If you want to read more about why this error occurs, check out [this section] ( this section ) of the docs.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

• SyntaxError: name 'X' is used prior to global declaration

Borislav Hadzhiev

Web Developer

Copyright © 2024 Borislav Hadzhiev

How to fix UnboundLocalError: local variable 'x' referenced before assignment in Python

by Nathan Sebhastian

Posted on May 26, 2023

Reading time: 2 minutes

One error you might encounter when running Python code is:

This error commonly occurs when you reference a variable inside a function without first assigning it a value.

You could also see this error when you forget to pass the variable as an argument to your function.

Let me show you an example that causes this error and how I fix it in practice.

How to reproduce this error

Suppose you have a variable called name declared in your Python code as follows:

Next, you created a function that uses the name variable as shown below:

When you execute the code above, you’ll get this error:

This error occurs because you both assign and reference a variable called name inside the function.

Python thinks you’re trying to assign the local variable name to name , which is not the case here because the original name variable we declared is a global variable.

How to fix this error

To resolve this error, you can change the variable’s name inside the function to something else. For example, name_with_title should work:

As an alternative, you can specify a name parameter in the greet() function to indicate that you require a variable to be passed to the function.

When calling the function, you need to pass a variable as follows:

This code allows Python to know that you intend to use the name variable which is passed as an argument to the function as part of the newly declared name variable.

Still, I would say that you need to use a different name when declaring a variable inside the function. Using the same name might confuse you in the future.

Here’s the best solution to the error:

Now it’s clear that we’re using the name variable given to the function as part of the value assigned to name_with_title . Way to go!

The UnboundLocalError: local variable 'x' referenced before assignment occurs when you reference a variable inside a function before declaring that variable.

To resolve this error, you need to use a different variable name when referencing the existing variable, or you can also specify a parameter for the function.

I hope this tutorial is useful. See you in other tutorials.

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Python local variable referenced before assignment Solution

When you start introducing functions into your code, you’re bound to encounter an UnboundLocalError at some point. This error is raised when you try to use a variable before it has been assigned in the local context .

In this guide, we talk about what this error means and why it is raised. We walk through an example of this error in action to help you understand how you can solve it.

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What is unboundlocalerror: local variable referenced before assignment.

Trying to assign a value to a variable that does not have local scope can result in this error:

Python has a simple rule to determine the scope of a variable. If a variable is assigned in a function , that variable is local. This is because it is assumed that when you define a variable inside a function you only need to access it inside that function.

There are two variable scopes in Python: local and global. Global variables are accessible throughout an entire program; local variables are only accessible within the function in which they are originally defined.

Let’s take a look at how to solve this error.

An Example Scenario

We’re going to write a program that calculates the grade a student has earned in class.

We start by declaring two variables:

These variables store the numerical and letter grades a student has earned, respectively. By default, the value of “letter” is “F”. Next, we write a function that calculates a student’s letter grade based on their numerical grade using an “if” statement :

Finally, we call our function:

This line of code prints out the value returned by the calculate_grade() function to the console. We pass through one parameter into our function: numerical. This is the numerical value of the grade a student has earned.

Let’s run our code and see what happens:

An error has been raised.

The Solution

Our code returns an error because we reference “letter” before we assign it.

We have set the value of “numerical” to 42. Our if statement does not set a value for any grade over 50. This means that when we call our calculate_grade() function, our return statement does not know the value to which we are referring.

We do define “letter” at the start of our program. However, we define it in the global context. Python treats “return letter” as trying to return a local variable called “letter”, not a global variable.

We solve this problem in two ways. First, we can add an else statement to our code. This ensures we declare “letter” before we try to return it:

Let’s try to run our code again:

Our code successfully prints out the student’s grade.

If you are using an “if” statement where you declare a variable, you should make sure there is an “else” statement in place. This will make sure that even if none of your if statements evaluate to True, you can still set a value for the variable with which you are going to work.

Alternatively, we could use the “global” keyword to make our global keyword available in the local context in our calculate_grade() function. However, this approach is likely to lead to more confusing code and other issues. In general, variables should not be declared using “global” unless absolutely necessary . Your first, and main, port of call should always be to make sure that a variable is correctly defined.

In the example above, for instance, we did not check that the variable “letter” was defined in all use cases.

That’s it! We have fixed the local variable error in our code.

The UnboundLocalError: local variable referenced before assignment error is raised when you try to assign a value to a local variable before it has been declared. You can solve this error by ensuring that a local variable is declared before you assign it a value.

Now you’re ready to solve UnboundLocalError Python errors like a professional developer !

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Local variable referenced before assignment in Python

The “local variable referenced before assignment” error occurs when you try to use a local variable before it has been assigned a value. This is a general programming concept describing the situation typically arises in situations where you declare a variable within a function but then try to access or modify it before actually assigning a value to it.

In Python, the compiler might throw the exact error: “UnboundLocalError: cannot access local variable ‘x’ where it is not associated with a value”

Here’s an example to illustrate this error:

In this example, you would encounter the above error because you’re trying to print the value of x before it has been assigned a value. To fix this, you should assign a value to x before attempting to access it:

In the corrected version, the local variable x is assigned a value before it’s used, preventing the error.

Keep in mind that Python treats variables inside functions as local unless explicitly stated otherwise using the global keyword (for global variables) or the nonlocal keyword (for variables in nested functions).

If you encounter this error and you’re sure that the variable should have been assigned a value before its use, double-check your code for any logical errors or typos that might be causing the variable to not be assigned properly.

Using the global keyword

If you have a global variable named letter and you try to modify it inside a function without declaring it as global, you will get error.

This is because Python assumes that any variable that is assigned a value inside a function is a local variable, unless you explicitly tell it otherwise.

To fix this error, you can use the global keyword to indicate that you want to use the global variable:

Using nonlocal keyword

The nonlocal keyword is used to work with variables inside nested functions, where the variable should not belong to the inner function. It allows you to modify the value of a non-local variable in the outer scope.

For example, if you have a function outer that defines a variable x , and another function inner inside outer that tries to change the value of x , you need to use the nonlocal keyword to tell Python that you are referring to the x defined in outer , not a new local variable in inner .

Here is an example of how to use the nonlocal keyword:

If you don’t use the nonlocal keyword, Python will create a new local variable x in inner , and the value of x in outer will not be changed:

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How to Solve Error - Local Variable Referenced Before Assignment in Python

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• How to Solve Error - Local Variable …

Check the Variable Scope to Fix the local variable referenced before assignment Error in Python

Initialize the variable before use to fix the local variable referenced before assignment error in python, use conditional assignment to fix the local variable referenced before assignment error in python.

This article delves into various strategies to resolve the common local variable referenced before assignment error. By exploring methods such as checking variable scope, initializing variables before use, conditional assignments, and more, we aim to equip both novice and seasoned programmers with practical solutions.

Each method is dissected with examples, demonstrating how subtle changes in code can prevent this frequent error, enhancing the robustness and readability of your Python projects.

The local variable referenced before assignment occurs when some variable is referenced before assignment within a function’s body. The error usually occurs when the code is trying to access the global variable.

The primary purpose of managing variable scope is to ensure that variables are accessible where they are needed while maintaining code modularity and preventing unexpected modifications to global variables.

We can declare the variable as global using the global keyword in Python. Once the variable is declared global, the program can access the variable within a function, and no error will occur.

The below example code demonstrates the code scenario where the program will end up with the local variable referenced before assignment error.

In this example, my_var is a global variable. Inside update_var , we attempt to modify it without declaring its scope, leading to the Local Variable Referenced Before Assignment error.

We need to declare the my_var variable as global using the global keyword to resolve this error. The below example code demonstrates how the error can be resolved using the global keyword in the above code scenario.

In the corrected code, we use the global keyword to inform Python that my_var references the global variable.

When we first print my_var , it displays the original value from the global scope.

After assigning a new value to my_var , it updates the global variable, not a local one. This way, we effectively tell Python the scope of our variable, thus avoiding any conflicts between local and global variables with the same name.

Ensure that the variable is initialized with some value before using it. This can be done by assigning a default value to the variable at the beginning of the function or code block.

The main purpose of initializing variables before use is to ensure that they have a defined state before any operations are performed on them. This practice is not only crucial for avoiding the aforementioned error but also promotes writing clear and predictable code, which is essential in both simple scripts and complex applications.

In this example, the variable total is used in the function calculate_total without prior initialization, leading to the Local Variable Referenced Before Assignment error. The below example code demonstrates how the error can be resolved in the above code scenario.

In our corrected code, we initialize the variable total with 0 before using it in the loop. This ensures that when we start adding item values to total , it already has a defined state (in this case, 0).

This initialization is crucial because it provides a starting point for accumulation within the loop. Without this step, Python does not know the initial state of total , leading to the error.

Conditional assignment allows variables to be assigned values based on certain conditions or logical expressions. This method is particularly useful when a variable’s value depends on certain prerequisites or states, ensuring that a variable is always initialized before it’s used, thereby avoiding the common error.

In this example, message is only assigned within the if and elif blocks. If neither condition is met (as with guest ), the variable message remains uninitialized, leading to the Local Variable Referenced Before Assignment error when trying to print it.

The below example code demonstrates how the error can be resolved in the above code scenario.

In the revised code, we’ve included an else statement as part of our conditional logic. This guarantees that no matter what value user_type holds, the variable message will be assigned some value before it is used in the print function.

This conditional assignment ensures that the message is always initialized, thereby eliminating the possibility of encountering the Local Variable Referenced Before Assignment error.

Throughout this article, we have explored multiple approaches to address the Local Variable Referenced Before Assignment error in Python. From the nuances of variable scope to the effectiveness of initializations and conditional assignments, these strategies are instrumental in developing error-free code.

The key takeaway is the importance of understanding variable scope and initialization in Python. By applying these methods appropriately, programmers can not only resolve this specific error but also enhance the overall quality and maintainability of their code, making their programming journey smoother and more rewarding.

Python UnboundLocalError: local variable referenced before assignment

by Suf | Programming , Python , Tips

If you try to reference a local variable before assigning a value to it within the body of a function, you will encounter the UnboundLocalError: local variable referenced before assignment.

The preferable way to solve this error is to pass parameters to your function, for example:

Alternatively, you can declare the variable as global to access it while inside a function. For example,

This tutorial will go through the error in detail and how to solve it with code examples .

Table of contents

What is scope in python, unboundlocalerror: local variable referenced before assignment, solution #1: passing parameters to the function, solution #2: use global keyword, solution #1: include else statement, solution #2: use global keyword.

Scope refers to a variable being only available inside the region where it was created. A variable created inside a function belongs to the local scope of that function, and we can only use that variable inside that function.

A variable created in the main body of the Python code is a global variable and belongs to the global scope. Global variables are available within any scope, global and local.

UnboundLocalError occurs when we try to modify a variable defined as local before creating it. If we only need to read a variable within a function, we can do so without using the global keyword. Consider the following example that demonstrates a variable var created with global scope and accessed from test_func :

If we try to assign a value to var within test_func , the Python interpreter will raise the UnboundLocalError:

This error occurs because when we make an assignment to a variable in a scope, that variable becomes local to that scope and overrides any variable with the same name in the global or outer scope.

var +=1 is similar to var = var + 1 , therefore the Python interpreter should first read var , perform the addition and assign the value back to var .

var is a variable local to test_func , so the variable is read or referenced before we have assigned it. As a result, the Python interpreter raises the UnboundLocalError.

Example #1: Accessing a Local Variable

Let’s look at an example where we define a global variable number. We will use the increment_func to increase the numerical value of number by 1.

Let’s run the code to see what happens:

The error occurs because we tried to read a local variable before assigning a value to it.

We can solve this error by passing a parameter to increment_func . This solution is the preferred approach. Typically Python developers avoid declaring global variables unless they are necessary. Let’s look at the revised code:

We have assigned a value to number and passed it to the increment_func , which will resolve the UnboundLocalError. Let’s run the code to see the result:

We successfully printed the value to the console.

We also can solve this error by using the global keyword. The global statement tells the Python interpreter that inside increment_func , the variable number is a global variable even if we assign to it in increment_func . Let’s look at the revised code:

Let’s run the code to see the result:

Example #2: Function with if-elif statements

Let’s look at an example where we collect a score from a player of a game to rank their level of expertise. The variable we will use is called score and the calculate_level function takes in score as a parameter and returns a string containing the player’s level .

In the above code, we have a series of if-elif statements for assigning a string to the level variable. Let’s run the code to see what happens:

The error occurs because we input a score equal to 40 . The conditional statements in the function do not account for a value below 55 , therefore when we call the calculate_level function, Python will attempt to return level without any value assigned to it.

We can solve this error by completing the set of conditions with an else statement. The else statement will provide an assignment to level for all scores lower than 55 . Let’s look at the revised code:

In the above code, all scores below 55 are given the beginner level. Let’s run the code to see what happens:

We can also create a global variable level and then use the global keyword inside calculate_level . Using the global keyword will ensure that the variable is available in the local scope of the calculate_level function. Let’s look at the revised code.

In the above code, we put the global statement inside the function and at the beginning. Note that the “default” value of level is beginner and we do not include the else statement in the function. Let’s run the code to see the result:

Congratulations on reading to the end of this tutorial! The UnboundLocalError: local variable referenced before assignment occurs when you try to reference a local variable before assigning a value to it. Preferably, you can solve this error by passing parameters to your function. Alternatively, you can use the global keyword.

If you have if-elif statements in your code where you assign a value to a local variable and do not account for all outcomes, you may encounter this error. In which case, you must include an else statement to account for the missing outcome.

For further reading on Python code blocks and structure, go to the article: How to Solve Python IndentationError: unindent does not match any outer indentation level .

Go to the  online courses page on Python  to learn more about Python for data science and machine learning.

Have fun and happy researching!

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4 ways to fix local variable referenced before assignment error in python, resolving the local variable referenced before assignment error in python.

Python is one of the world’s most popular programming languages due to its simplicity, readability, and versatility. Despite its many advantages, when coding in Python, one may encounter various errors, with the most common being the “local variable referenced before assignment” error.

Even the most experienced Python developers have encountered this error at some point in their programming career. In this article, we will look at four effective strategies for resolving the local variable referenced before assignment error in Python.

Strategy 1: Assigning a Value before Referencing

The first strategy is to assign a value to a variable before referencing it. The error occurs when the variable is referenced before it is assigned a value.

This problem can be avoided by initializing the variable before referencing it. For example, let us consider the snippet below:

“`python

add_numbers():

print(x + y)

add_numbers()

In the snippet above, the variables `x` and `y` are not assigned values before they are referenced in the `print` statement. Therefore, we will get a local variable “referenced before assignment” error.

To resolve this error, we must initialize the variables before referencing them. We can avoid this error by assigning a value to `x` and `y` before they are referenced, as shown below:

Strategy 2: Using the Global Keyword

In Python, variables declared inside a function are considered local variables. Thus, they are separate from other variables declared outside of the function.

If we want to use a variable outside of the function, we must use the global keyword. Using the global keyword tells Python that you want to use the variable that was defined globally, not locally.

For example:

In the code snippet above, the `global` keyword tells Python to use the variable `x` defined outside of the function rather than a local variable named `x`. Thus, Python will output 30.

Strategy 3: Adding Input Parameters for Functions

Another way to avoid the local variable referenced before assignment error is by adding input parameters to functions.

def add_numbers(x, y):

add_numbers(10, 20)

In the code snippet above, `x` and `y` are variables that are passed into the `add_numbers` function as arguments.

This approach allows us to avoid the local variable referenced before assignment error because the variables are being passed into the function as input parameters. Strategy 4: Initializing Variables before Loops or Conditionals

Finally, it’s also a good practice to initialize the variables before loops or conditionals.

If you are defining a variable within a loop, you must initialize it before the loop starts. This way, the variable already exists, and we can update the value inside the loop.

my_list = [1, 2, 3, 4, 5]

for number in my_list:

sum += number

In the code snippet above, the variable `sum` has been initialized with the value of 0 before the loop runs. Thus, we can update and use the variable inside the loop.

In conclusion, the “local variable referenced before assignment” error is a common issue in Python. However, with the strategies discussed in this article, you can avoid the error and write clean Python code.

Remember to initialize your variables, use the global keyword, add input parameters in functions, and initialize variables before loops or conditionals. By following these techniques, your Python code will be error-free and much easier to manage.

In essence, this article has provided four key strategies for resolving the “local variable referenced before assignment” error that is common in Python. These strategies include initializing variables before referencing, using the global keyword, adding input parameters to functions, and initializing variables before loops or conditionals.

These techniques help to ensure clean code that is free from errors. By implementing these strategies, developers can improve their code quality and avoid time-wasting errors that can occur in their work.

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What is UnboundLocalError: local variable referenced before assignment?

Trying to assign a value to a variable that does not have local scope can result in this error:

Python has a simple rule to determine the scope of a variable. To clarify, a variable is assigned in a function, that variable is local. Because it is assumed that when you define a variable inside a function, you only need to access it inside that function.

There are two variable scopes in Python: local and global. Global variables are accessible throughout an entire program. Whereas, local variables are only accessible within the function in which they are originally defined.

An example of Local variable referenced before assignment

We’re going to write a program that calculates the grade a student has earned in class.

Firstly, we start by declaring two variables:

These variables store the numerical and letter grades a student has earned, respectively. By default, the value of “letter” is “F”. Then, we write a function that calculates a student’s letter grade based on their numerical grade using an “if” statement:

Finally, we call our function:

This line of code prints out the value returned by the  calculate_grade()  function to the console. We pass through one parameter into our function: numerical. This is the numerical value of the grade a student has earned.

Let’s run our code of Local variable referenced before assignment and see what happens:

Here is an error!

The Solution of Local variable referenced before assignment

The code returns an error: Unboundlocalerror local variable referenced before assignment because we reference “letter” before we assign it.

We have set the value of “numerical” to 42. Our  if  statement does not set a value for any grade over 50. This means that when we call our  calculate_grade()  function, our return statement does not know the value to which we are referring.

Moreover, we do define “letter” at the start of our program. However, we define it in the global context. Because Python treats “return letter” as trying to return a local variable called “letter”, not a global variable.

Therefore, this problem of variable referenced before assignment could be solved in two ways. Firstly, we can add an  else  statement to our code. This ensures we declare “letter” before we try to return it:

Let’s try to run our code again:

Our code successfully prints out the student’s grade. This approach is good because it lets us keep “letter” in the local context. To clarify, we could even remove the “letter = “F”” statement from the top of our code because we do not use it in the global context.

Alternatively, we could use the “global” keyword to make our global keyword available in the local context in our  calculate_grade()  function:

We use the “global” keyword at the start of our function.

This keyword changes the scope of our variable to a global variable. This means the “return” statement will no longer treat “letter” like a local variable. Let’s run our code. Our code returns: F.

The code works successfully! Let’s try it using a different grade number by setting the value of “numerical” to a new number:

Our code returns: B.

Finally, we have fixed the local variable referenced before assignment error in the code.

To sum up, as you can see, the UnboundLocalError: local variable referenced before assignment error is raised when you try to assign a value to a local variable before it has been declared. Then, you can solve this error by ensuring that a local variable is declared before you assign it a value. Moreover, if a variable is declared globally that you want to access in a function, you can use the “global” keyword to change its value. In case you have any inquiry, let’s CONTACT US . With a lot of experience in Mobile app development services , we will surely solve it for you instantly.

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Global and Local Variables in Python

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Python Global variables are those which are not defined inside any function and have a global scope whereas Python local variables are those which are defined inside a function and their scope is limited to that function only. In other words, we can say that local variables are accessible only inside the function in which it was initialized whereas the global variables are accessible throughout the program and inside every function. 

Python Local Variables

Local variables in Python are those which are initialized inside a function and belong only to that particular function. It cannot be accessed anywhere outside the function. Let’s see how to create a local variable.

Creating local variables in Python

Defining and accessing local variables

Can a local variable be used outside a function?

If we will try to use this local variable outside the function then let’s see what will happen.

Python Global Variables

These are those which are defined outside any function and which are accessible throughout the program, i.e., inside and outside of every function. Let’s see how to create a Python global variable.

Create a global variable  in Python

Defining and accessing Python global variables.

The variable s is defined as the global variable and is used both inside the function as well as outside the function.

Note: As there are no locals, the value from the globals will be used but make sure both the local and the global variables should have same name.

Why do we use Local and Global variables in Python?

Now, what if there is a Python variable with the same name initialized inside a function as well as globally? Now the question arises, will the local variable will have some effect on the global variable or vice versa, and what will happen if we change the value of a variable inside of the function f()? Will it affect the globals as well? We test it in the following piece of code: 

If a variable with the same name is defined inside the scope of the function as well then it will print the value given inside the function only and not the global value. 

Now, what if we try to change the value of a global variable inside the function? Let’s see it using the below example.

To make the above program work, we need to use the “global” keyword in Python. Let’s see what this global keyword is.

The global Keyword

We only need to use the global keyword in a function if we want to do assignments or change the global variable. global is not needed for printing and accessing. Python “assumes” that we want a local variable due to the assignment to s inside of f(), so the first statement throws the error message. Any variable which is changed or created inside of a function is local if it hasn’t been declared as a global variable. To tell Python, that we want to use the global variable, we have to use the keyword “global” , as can be seen in the following example: 

Example 1: Using Python global keyword

Now there is no ambiguity. 

Example 2: Using Python global and local variables

Difference b/w Local Variable Vs. Global Variables

Please login to comment..., similar reads, improve your coding skills with practice.

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Local variable 'j' referenced before assignment after "j in range(n)"

I have a question, unrelated to the whole program. The following program can work, but if I replace s_out += str(n-i) + s[n-1] with s_out += str(j+1-i) + s[j] , it won’t work. Why not? After a loop, j and (n-1) should be equivalent. I got an error “local variable ‘j’ referenced before assignment”.

I thought it was because j was not predefined before range(n), but the following program does work:

PS: I hate the usage of the class here, which does nothing. It is how Lxxxcode uses it, and I just copy it.

The loop variable will only exist if there is any looping:

If the string is empty “” and n=0, the for loop doesn’t run and j never gets a value assigned at all.

Outside of a function, you get a NameError.

Inside a function, you get UnboundLocalError, which is a subclass of NameError.

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导出模型有问题,local variable 'model' referenced before assignment #502

monkeycc commented May 11, 2023

LauraGPT commented May 11, 2023

Sorry, something went wrong.

LRY1994 commented Mar 11, 2024

Lauragpt commented mar 11, 2024.

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• précédent |
• Python »
• 3.14.0a0 Documentation »
• La bibliothèque standard »
• Débogueur et instrumentation »
• pdb — Le débogueur Python
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pdb — Le débogueur Python ¶

Code source : Lib/pdb.py

Le module pdb définit un débogueur de code source interactif pour les programmes Python. Il supporte le paramétrage (conditionnel) de points d'arrêt et l'exécution du code source ligne par ligne, l'inspection des frames de la pile, la liste du code source, et l'évaluation arbitraire de code Python dans le contexte de n'importe quelle frame de la pile. Il supporte aussi le débogage post-mortem et peut être contrôlé depuis un programme.

Le débogueur est extensible -- Il est en réalité défini comme la classe Pdb . C'est actuellement non-documenté mais facilement compréhensible en lisant le code source. L'interface d'extension utilise les modules bdb et cmd .

Used to dump Python tracebacks explicitly, on a fault, after a timeout, or on a user signal.

Standard interface to extract, format and print stack traces of Python programs.

The typical usage to break into the debugger is to insert:

at the location you want to break into the debugger, and then run the program. You can then step through the code following this statement, and continue running without the debugger using the continue command.

Modifié dans la version 3.7: La fonction standard breakpoint() , quand elle est appelée avec les valeurs par défaut, peut être utilisée en lieu et place de import pdb; pdb.set_trace() .

The debugger's prompt is (Pdb) , which is the indicator that you are in debug mode:

Modifié dans la version 3.3: La complétion via le module readline est disponible pour les commandes et les arguments de commande, par exemple les noms global et local sont proposés comme arguments de la commande p .

You can also invoke pdb from the command line to debug other scripts. For example:

When invoked as a module, pdb will automatically enter post-mortem debugging if the program being debugged exits abnormally. After post-mortem debugging (or after normal exit of the program), pdb will restart the program. Automatic restarting preserves pdb's state (such as breakpoints) and in most cases is more useful than quitting the debugger upon program's exit.

Modifié dans la version 3.2: Added the -c option to execute commands as if given in a .pdbrc file; see Commande du débogueur .

Modifié dans la version 3.7: Added the -m option to execute modules similar to the way python -m does. As with a script, the debugger will pause execution just before the first line of the module.

Typical usage to execute a statement under control of the debugger is:

L'usage typique pour inspecter un programme planté :

Modifié dans la version 3.13: The implementation of PEP 667 means that name assignments made via pdb will immediately affect the active scope, even when running inside an optimized scope .

Le module définit les fonctions suivantes; chacune entre dans le débogueur d'une manière légèrement différente :

Exécute la déclaration (donnée sous forme de chaîne de caractères ou d'objet code) sous le contrôle du débogueur. L'invite de débogage apparaît avant l'exécution de tout code; vous pouvez définir des points d'arrêt et taper continue , ou vous pouvez passer à travers l'instruction en utilisant step ou next (toutes ces commandes sont expliquées ci-dessous). Les arguments globals et locals optionnels spécifient l'environnement dans lequel le code est exécuté; par défaut le dictionnaire du module __main__ est utilisé. (Voir l'explication des fonctions natives exec() ou eval() .)

Evaluate the expression (given as a string or a code object) under debugger control. When runeval() returns, it returns the value of the expression . Otherwise this function is similar to run() .

Appelle la function (une fonction ou une méthode, pas une chaine de caractères) avec les arguments donnés. Quand runcall() revient, il retourne ce que l'appel de fonctionne a renvoyé. L'invite de débogage apparaît dès que la fonction est entrée.

Invoque le débogueur dans la cadre d'exécution appelant. C'est utile pour coder en dur un point d'arrêt dans un programme, même si le code n'est pas autrement débogué (par exemple, quand une assertion échoue). S'il est donné, header est affiché sur la console juste avant que le débogage commence.

Modifié dans la version 3.7: L’argument keyword-only header .

Modifié dans la version 3.13: set_trace() will enter the debugger immediately, rather than on the next line of code to be executed.

Entre le débogage post-mortem de l'objet traceback donné. Si aucun traceback n'est donné, il utilise celui de l'exception en cours de traitement (une exception doit être gérée si la valeur par défaut doit être utilisée).

Enter post-mortem debugging of the exception found in sys.last_exc .

Les fonctions run* et set_trace() sont des alias pour instancier la classe Pdb et appeler la méthode du même nom. Si vous souhaitez accéder à d'autres fonctionnalités, vous devez le faire vous-même :

Le classe du débogueur est la classe Pdb .

Les arguments completekey , stdin et stdout sont transmis à la classe sous-jacente cmd.Cmd ; voir la description ici.

L'argument skip , s'il est donné, doit être un itérable des noms de modules de style glob . Le débogueur n'entrera pas dans les frames qui proviennent d'un module qui correspond à l'un de ces motifs. [ 1 ]

By default, Pdb sets a handler for the SIGINT signal (which is sent when the user presses Ctrl - C on the console) when you give a continue command. This allows you to break into the debugger again by pressing Ctrl - C . If you want Pdb not to touch the SIGINT handler, set nosigint to true.

L'argument readrc vaut True par défaut et contrôle si Pdb chargera les fichiers .pdbrc depuis le système de fichiers.

Exemple d'appel pour activer le traçage avec skip  :

Lève un évènement d'audit pdb.Pdb sans argument.

Modifié dans la version 3.1: Added the skip parameter.

Modifié dans la version 3.2: Added the nosigint parameter. Previously, a SIGINT handler was never set by Pdb.

Modifié dans la version 3.6: L'argument readrc .

Voir la documentation pour les fonctions expliquées ci-dessus.

Commande du débogueur ¶

Les commandes reconnues par le débogueur sont listées. La plupart des commandes peuvent être abrégées à une ou deux lettres comme indiquées; par exemple. h(elp) signifie que soit h ou help peut être utilisée pour entrer la commande help (mais pas he or hel , ni H ou HELP ). Les arguments des commandes doivent être séparées par des espaces (espaces ou tabulations). Les arguments optionnels sont entourés dans des crochets ( [] ) dans la syntaxe de la commande; les crochets ne doivent pas être insérés. Les alternatives dans la syntaxe de la commande sont séparés par une barre verticale ( | ).

Entrer une ligne vide répète la dernière commande entrée. Exception: si la dernière commande était la commande list , les 11 prochaines lignes sont affichées.

Les commandes que le débogueur ne reconnaît pas sont supposées être des instructions Python et sont exécutées dans le contexte du programme en cours de débogage. Les instructions Python peuvent également être préfixées avec un point d'exclamation ( ! ). C'est une façon puissante d'inspecter le programme en cours de débogage; il est même possible de changer une variable ou d'appeler une fonction. Lorsqu'une exception se produit dans une telle instruction, le nom de l'exception est affiché mais l'état du débogueur n'est pas modifié.

Modifié dans la version 3.13: Expressions/Statements whose prefix is a pdb command are now correctly identified and executed.

Le débogueur supporte aliases . Les alias peuvent avoir des paramètres qui permettent un certain niveau d'adaptabilité au contexte étudié.

Multiple commands may be entered on a single line, separated by ;; . (A single ; is not used as it is the separator for multiple commands in a line that is passed to the Python parser.) No intelligence is applied to separating the commands; the input is split at the first ;; pair, even if it is in the middle of a quoted string. A workaround for strings with double semicolons is to use implicit string concatenation ';'';' or ";"";" .

To set a temporary global variable, use a convenience variable . A convenience variable is a variable whose name starts with $ . For example, $foo = 1 sets a global variable $foo which you can use in the debugger session. The convenience variables are cleared when the program resumes execution so it's less likely to interfere with your program compared to using normal variables like foo = 1 .

There are three preset convenience variables :

$_frame : the current frame you are debugging

$_retval : the return value if the frame is returning

$_exception : the exception if the frame is raising an exception

Added in version 3.12: Added the convenience variable feature.

If a file .pdbrc exists in the user's home directory or in the current directory, it is read with 'utf-8' encoding and executed as if it had been typed at the debugger prompt, with the exception that empty lines and lines starting with # are ignored. This is particularly useful for aliases. If both files exist, the one in the home directory is read first and aliases defined there can be overridden by the local file.

Modifié dans la version 3.2: Le fichier .pdbrc peut maintenant contenir des commandes qui continue le débogage, comme continue ou next . Précédemment, ces commandes n'avaient aucun effet.

Modifié dans la version 3.11: .pdbrc is now read with 'utf-8' encoding. Previously, it was read with the system locale encoding.

Sans argument, affiche la liste des commandes disponibles. Avec une commande comme argument, affiche l'aide de cette commande. help pdb affiche la documentation complète (la docstring du module pdb ). Puisque l'argument command doit être un identificateur, help exec doit être entré pour obtenir de l'aide sur la commande ! .

Print a stack trace, with the most recent frame at the bottom. An arrow ( > ) indicates the current frame, which determines the context of most commands.

Déplace le niveau de la frame courante count (par défaut un) vers le bas dans la trace de pile (vers une frame plus récente).

Déplace le niveau de la frame courante count (par défaut un) vers le haut dans la trace de pile (vers une frame plus ancienne).

With a lineno argument, set a break at line lineno in the current file. The line number may be prefixed with a filename and a colon, to specify a breakpoint in another file (possibly one that hasn't been loaded yet). The file is searched on sys.path . Accepatable forms of filename are /abspath/to/file.py , relpath/file.py , module and package.module .

With a function argument, set a break at the first executable statement within that function. function can be any expression that evaluates to a function in the current namespace.

Si un second argument est présent, c'est une expression qui doit évaluer à True avant que le point d'arrêt ne soit honoré.

Sans argument, liste tous les arrêts, incluant pour chaque point d'arrêt, le nombre de fois qu'un point d'arrêt a été atteint, le nombre de ignore, et la condition associée le cas échéant.

Each breakpoint is assigned a number to which all the other breakpoint commands refer.

Point d'arrêt temporaire, qui est enlevé automatiquement au premier passage. Les arguments sont les mêmes que pour break .

Avec un argument filename:lineno , efface tous les points d'arrêt sur cette ligne. Avec une liste de numéros de points d'arrêt séparés par un espace, efface ces points d'arrêt. Sans argument, efface tous les points d'arrêt (mais demande d'abord confirmation).

Désactive les points d'arrêt indiqués sous la forme d'une liste de numéros de points d'arrêt séparés par un espace. Désactiver un point d'arrêt signifie qu'il ne peut pas interrompre l'exécution du programme, mais à la différence d'effacer un point d'arrêt, il reste dans la liste des points d'arrêt et peut être (ré)activé.

Active les points d'arrêt spécifiés.

Set the ignore count for the given breakpoint number. If count is omitted, the ignore count is set to 0. A breakpoint becomes active when the ignore count is zero. When non-zero, the count is decremented each time the breakpoint is reached and the breakpoint is not disabled and any associated condition evaluates to true.

Définit une nouvelle condition pour le point d'arrêt, une expression qui doit évaluer à True avant que le point d'arrêt ne soit honoré. Si condition est absente, toute condition existante est supprimée, c'est-à-dire que le point d'arrêt est rendu inconditionnel.

Spécifie une liste de commandes pour le numéro du point d'arrêt bpnumber . Les commandes elles-mêmes apparaissent sur les lignes suivantes. Tapez une ligne contenant juste end pour terminer les commandes. Un exemple :

Pour supprimer toutes les commandes depuis un point d'arrêt, écrivez commands suivi immédiatement de end  ; ceci supprime les commandes.

Sans argument bpnumber , commands se réfère au dernier point d'arrêt défini.

Vous pouvez utiliser les commandes de point d'arrêt pour redémarrer votre programme. Utilisez simplement la commande continue , ou step , ou toute autre commande qui reprend l'exécution.

Entrer toute commande reprenant l'exécution (actuellement continue , step , next , return , jump , quit et leurs abréviations) termine la liste des commandes (comme si cette commande était immédiatement suivie de la fin). C'est parce que chaque fois que vous reprenez l'exécution (même avec un simple next ou step ), vous pouvez rencontrer un autre point d'arrêt -- qui pourrait avoir sa propre liste de commandes, conduisant à des ambiguïtés sur la liste à exécuter.

If you use the silent command in the command list, the usual message about stopping at a breakpoint is not printed. This may be desirable for breakpoints that are to print a specific message and then continue. If none of the other commands print anything, you see no sign that the breakpoint was reached.

Exécute la ligne en cours, s'arrête à la première occasion possible (soit dans une fonction qui est appelée, soit sur la ligne suivante de la fonction courante).

Continue l'exécution jusqu'à ce que la ligne suivante de la fonction en cours soit atteinte ou qu'elle revienne. (La différence entre next et step est que step s'arrête dans une fonction appelée, tandis que next exécute les fonctions appelées à (presque) pleine vitesse, ne s'arrêtant qu'à la ligne suivante dans la fonction courante.)

Sans argument, continue l'exécution jusqu'à ce que la ligne avec un nombre supérieur au nombre actuel soit atteinte.

With lineno , continue execution until a line with a number greater or equal to lineno is reached. In both cases, also stop when the current frame returns.

Modifié dans la version 3.2: Permet de donner un numéro de ligne explicite.

Continue l'exécution jusqu'au retour de la fonction courante.

Continue l'exécution, seulement s'arrête quand un point d'arrêt est rencontré.

Définit la prochaine ligne qui sera exécutée. Uniquement disponible dans la frame inférieur. Cela vous permet de revenir en arrière et d'exécuter à nouveau le code, ou de passer en avant pour sauter le code que vous ne voulez pas exécuter.

Il est à noter que tous les sauts ne sont pas autorisés -- par exemple, il n'est pas possible de sauter au milieu d'une boucle for ou en dehors d'une clause finally .

Liste le code source du fichier courant. Sans arguments, liste 11 lignes autour de la ligne courante ou continue le listing précédant. Avec l'argument . , liste 11 lignes autour de la ligne courante. Avec un argument, liste les 11 lignes autour de cette ligne. Avec deux arguments, liste la plage donnée; si le second argument est inférieur au premier, il est interprété comme un compte.

La ligne en cours dans l'image courante est indiquée par -> . Si une exception est en cours de débogage, la ligne où l'exception a été initialement levée ou propagée est indiquée par >> , si elle diffère de la ligne courante.

Modifié dans la version 3.2: Added the >> marker.

Liste le code source de la fonction ou du bloc courant. Les lignes intéressantes sont marquées comme pour list .

Added in version 3.2.

Print the arguments of the current function and their current values.

Evaluate expression in the current context and print its value.

print() peut aussi être utilisée, mais n'est pas une commande du débogueur --- il exécute la fonction Python print() .

Like the p command, except the value of expression is pretty-printed using the pprint module.

Print the type of expression .

Try to get source code of expression and display it.

Display the value of expression if it changed, each time execution stops in the current frame.

Without expression , list all display expressions for the current frame.

Display evaluates expression and compares to the result of the previous evaluation of expression , so when the result is mutable, display may not be able to pick up the changes.

Display won't realize lst has been changed because the result of evaluation is modified in place by lst.append(1) before being compared:

You can do some tricks with copy mechanism to make it work:

Do not display expression anymore in the current frame. Without expression , clear all display expressions for the current frame.

Start an interactive interpreter (using the code module) in a new global namespace initialised from the local and global namespaces for the current scope. Use exit() or quit() to exit the interpreter and return to the debugger.

As interact creates a new dedicated namespace for code execution, assignments to variables will not affect the original namespaces. However, modifications to any referenced mutable objects will be reflected in the original namespaces as usual.

Modifié dans la version 3.13: exit() and quit() can be used to exit the interact command.

Modifié dans la version 3.13: interact directs its output to the debugger's output channel rather than sys.stderr .

Create an alias called name that executes command . The command must not be enclosed in quotes. Replaceable parameters can be indicated by %1 , %2 , ... and %9 , while %* is replaced by all the parameters. If command is omitted, the current alias for name is shown. If no arguments are given, all aliases are listed.

Les alias peuvent être imbriqués et peuvent contenir tout ce qui peut être légalement tapé à l'invite pdb . Notez que les commandes pdb internes peuvent être remplacées par des alias. Une telle commande est alors masquée jusqu'à ce que l'alias soit supprimé. L' aliasing est appliqué récursivement au premier mot de la ligne de commande; tous les autres mots de la ligne sont laissés seuls.

Comme un exemple, voici deux alias utiles (spécialement quand il est placé dans le fichier .pdbrc ) :

Delete the specified alias name .

Execute the (one-line) statement in the context of the current stack frame. The exclamation point can be omitted unless the first word of the statement resembles a debugger command, e.g.:

To set a global variable, you can prefix the assignment command with a global statement on the same line, e.g.:

Restart the debugged Python program. If args is supplied, it is split with shlex and the result is used as the new sys.argv . History, breakpoints, actions and debugger options are preserved. restart is an alias for run .

Quitte le débogueur. Le programme exécuté est arrêté.

Enter a recursive debugger that steps through code (which is an arbitrary expression or statement to be executed in the current environment).

Print the return value for the last return of the current function.

List or jump between chained exceptions.

When using pdb.pm() or Pdb.post_mortem(...) with a chained exception instead of a traceback, it allows the user to move between the chained exceptions using exceptions command to list exceptions, and exception <number> to switch to that exception.

calling pdb.pm() will allow to move between exceptions:

Added in version 3.13.

Table des matières

• Commande du débogueur

Sujet précédent

faulthandler --- Dump the Python traceback

Sujet suivant

The Python Profilers

• Signalement de bogue
• Voir la source