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UnboundLocalError Local variable Referenced Before Assignment in Python

Handling errors is an integral part of writing robust and reliable Python code. One common stumbling block that developers often encounter is the “UnboundLocalError” raised within a try-except block. This error can be perplexing for those unfamiliar with its nuances but fear not – in this article, we will delve into the intricacies of the UnboundLocalError and provide a comprehensive guide on how to effectively use try-except statements to resolve it.

What is UnboundLocalError Local variable Referenced Before Assignment in Python?

The UnboundLocalError occurs when a local variable is referenced before it has been assigned a value within a function or method. This error typically surfaces when utilizing try-except blocks to handle exceptions, creating a puzzle for developers trying to comprehend its origins and find a solution.

Why does UnboundLocalError: Local variable Referenced Before Assignment Occur?

below, are the reasons of occurring “Unboundlocalerror: Try Except Statements” in Python :

Variable Assignment Inside Try Block

Reassigning a global variable inside except block.

  • Accessing a Variable Defined Inside an If Block

In the below code, example_function attempts to execute some_operation within a try-except block. If an exception occurs, it prints an error message. However, if no exception occurs, it prints the value of the variable result outside the try block, leading to an UnboundLocalError since result might not be defined if an exception was caught.

In below code , modify_global function attempts to increment the global variable global_var within a try block, but it raises an UnboundLocalError. This error occurs because the function treats global_var as a local variable due to the assignment operation within the try block.

Solution for UnboundLocalError Local variable Referenced Before Assignment

Below, are the approaches to solve “Unboundlocalerror: Try Except Statements”.

Initialize Variables Outside the Try Block

Avoid reassignment of global variables.

In modification to the example_function is correct. Initializing the variable result before the try block ensures that it exists even if an exception occurs within the try block. This helps prevent UnboundLocalError when trying to access result in the print statement outside the try block.

 

Below, code calculates a new value ( local_var ) based on the global variable and then prints both the local and global variables separately. It demonstrates that the global variable is accessed directly without being reassigned within the function.

In conclusion , To fix “UnboundLocalError” related to try-except statements, ensure that variables used within the try block are initialized before the try block starts. This can be achieved by declaring the variables with default values or assigning them None outside the try block. Additionally, when modifying global variables within a try block, use the `global` keyword to explicitly declare them.

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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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Local variable referenced before assignment in Python

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

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# 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 .

unboundlocalerror local variable name referenced before assignment

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.

mark variable as global

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 global variables in functions

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.

variables declared in function cannot be accessed in 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.

return value from the function

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.

pass global variable as argument to 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.

assign value to local variable from outer scope

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.

not using nonlocal prints 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

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

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

How to reproduce this error

How to fix this error.

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

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[SOLVED] Local Variable Referenced Before Assignment

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 VariablesGlobal Variables
A variable is declared primarily within a Python function.Global variables are in the global scope, outside a function.
A local variable is created when the function is called and destroyed when the execution is finished.A Variable is created upon execution and exists in memory till the program stops.
Local Variables can only be accessed within their own function.All functions of the program can access global variables.
Local variables are immune to changes in the global scope. Thereby being more secure.Global Variables are less safer from manipulation as they are accessible in the global scope.

[Fixed] typeerror can’t compare datetime.datetime to datetime.date

Local Variable Referenced Before Assignment Error with Explanation

Try these examples yourself using our Online Compiler.

Let’s look at the following function:

Local Variable Referenced Before Assignment Error

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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[Fixed] nameerror: name Unicode is not defined

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Python 3: UnboundLocalError: local variable referenced before assignment

This error occurs when you are trying to access a variable before it has been assigned a value. Here is an example of a code snippet that would raise this error:

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The error message will be:

In this example, the variable x is being accessed before it is assigned a value, which is causing the error. To fix this, you can either move the assignment of the variable x before the print statement, or give it an initial value before the print statement.

Both will work without any error.

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【Python】成功解决python报错:UnboundLocalError: local variable ‘xxx‘ referenced before assignment

unboundlocalerror local variable 'ip' referenced before assignment

成功解决python报错:UnboundLocalError: local variable ‘xxx’ referenced before assignment。在Python中, UnboundLocalError 是一种特定的 NameError ,它会在尝试引用一个还未被赋值的局部变量时发生。Python解释器需要知道变量的类型和作用域,因此,在局部作用域内引用一个未被赋值的变量时,就会抛出这个错误。

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【Python】解决Python报错:

1. 什么是unboundlocalerror?, 2. 常见的场景和原因, 方法一:全局变量, 方法二:函数参数, 方法三:局部变量初始化, 方法四:结合条件语句.

在这里插入图片描述

在Python编程中, UnboundLocalError: local variable 'xxx' referenced before assignment 是一个常见的错误,尤其是在写函数时可能会遇到。这篇技术博客将详细介绍 UnboundLocalError ,为什么会发生,以及如何解决这个错误。

在Python中, UnboundLocalError 是一种特定的 NameError ,它会在尝试引用一个还未被赋值的局部变量时发生。Python解释器需要知道变量的类型和作用域,因此,在局部作用域内引用一个未被赋值的变量时,就会抛出这个错误。

这是一个简单的代码示例来说明这个错误:

运行以上代码会抛出以下错误:

在这个例子中,Python解释器看到 print(x) 时,寻找局部作用域中的变量 x ,但这个变量在局部作用域内尚未被赋值(虽然在后面有赋值,解释器是从上到下执行代码的)。

理解错误的原因后,可以通过以下几种方式来解决 UnboundLocalError :

如果变量希望在函数内和函数外都使用,可以将其声明为全局变量:

通过在函数内使用 global 关键字,将 x 声明为全局变量,这样即使在函数内也能访问全局变量 x 。

通过将变量作为参数传递给函数,使得函数内可以访问并使用这个变量:

在这种情况下, x 是函数 my_function 的一个参数,无需在函数内部声明。

在使用变量之前,先初始化该局部变量:

确保在函数内部引用变量之前,该变量已经被赋值。

在复杂的逻辑中,特别是在涉及条件语句时,可以先在函数开始部分初始化变量,确保无论哪条路径都可以正确访问该变量:

在这个例子中,我们确保了变量 x 在函数内部任何地方都能被适当地引用。

  • 命名冲突 :在全局变量和局部变量重名情况下,优先使用局部变量。如果不小心混用,容易引发错误。
  • 提前规划变量作用域 :代码设计时,可以提前规划好变量应该属于哪个作用域,以减少变量冲突和未定义变量的情况。

UnboundLocalError: local variable 'xxx' referenced before assignment 错误是一个常见的初学者错误,但只要理解了Python的变量作用域规则和执行顺序,就可以轻松避开。通过合适的解决方法,如使用全局变量、函数参数、局部变量初始化或结合条件语句,可以高效且清晰地管理变量的使用。

希望这篇文章能帮助你理解和解决这个错误。如果有任何问题或其他建议,欢迎在评论中与我们讨论。Happy coding!

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UndboundLocalError: local variable referenced before assignment

Hello all, I’m using PsychoPy 2023.2.3 Win 10 x64bits

image

What I’m trying to do? The experiment will show in the middle of the screen an abstracted stimuli (B1 or B2), and after valid click on it, the stimulus will remain on the middle of the screen and three more stimuli will appear in the cornor of the screen.

I’m having this erro (attached above), a simple error, but I can not see where the error is. Also the experiment isn’t working proberly and is the old version (I don’t know but someone are having troubles with this version of PscyhoPy)? ba_training_block.xlsx (13.8 KB) SMTS.psyexp (91.6 KB) stimuli, instructions and parameters.xlsx (12.8 KB)

You have a routine called sample but you also use that name for your image file in sample_box .

I changed the name of the routine for ‘stimulus_sample’ and manteined the image file in sample_box as ‘sample’. But, the error still remain. But it do not happen all the time, this is very interesting…

Can u give it a look again? (I made some minor changes here)

image

Here the exp file ba_training_block.xlsx (13.7 KB) SMTS.psyexp (89.7 KB) stimuli, instructions and parameters.xlsx (12.8 KB)

Thanks again

Please could you confirm/show the new error message? Is it definitely still related to sample?

image

I think you have blank rows in your spreadsheet. The loop claims that there are 19 conditions but I think you only want 12. Without a value for sample_category sample doesn’t get set. With random presentation this will happen at a random point.

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having a problem with error code: UnboundLocalError: local variable 'player' referenced before assignment

hi hoping someone here can actually help me. I asked this question on stack overflow and they closed it and redirected to similar previously asked questions. none of which actually helped me to understand how to correct the error code.

I am following a video tutorial series for learning to code with python/pygame. and i have checked my coding aginst the source material and they are the same, because i typed it as was told to in the video.

here's the full tracebackback including the error:

File "/home/dev/PycharmProjects/game7_meteor_game/game7_meteor_game.py", line 160, in <module>

File "/home/dev/PycharmProjects/game7_meteor_game/game7_meteor_game.py", line 152, in main

GameInterface(num_player=1, screen=screen)

File "/home/dev/PycharmProjects/game7_meteor_game/game7_meteor_game.py", line 82, in GameInterface

if player.cooling_time > 0:

UnboundLocalError: local variable 'player' referenced before assignment.

here's the actual code:

if player.cooling_time > 0: player.cooling_time -= 1

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UnboundLocalError: local variable 'conn' referenced before assignment [duplicate]

I have an error (shown in title) which occurs when I run this script:

conn has global scope, and is assigned to None before being referenced in the function - why the error message?

Homunculus Reticulli's user avatar

  • You haven't pasted in the whole function body. The problem arises because you are rebinding the variable later on in this scope –  John La Rooy Commented Dec 21, 2011 at 9:42

In python you have to declare your global variables which you want to alter in functions with the global keyword:

My guess is that you are going to assign some value to conn somewhere later in the function, so you have to use the global keyword.

Constantinius's user avatar

  • 2 Wow, I never seen that before - looks kinda like PHP :) –  Homunculus Reticulli Commented Dec 21, 2011 at 9:34
  • That is only required if you wish to rebind the variable –  John La Rooy Commented Dec 21, 2011 at 9:34
  • @gnibbler: yes of course. But I think that is what OP is doing later in the function. –  Constantinius Commented Dec 21, 2011 at 9:35
  • 1 I think you are correct. It is confusing the first time you see it because the error comes from the first time the variable is used rather than when it is assigned to –  John La Rooy Commented Dec 21, 2011 at 9:41

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unboundlocalerror local variable 'ip' referenced before assignment

COMMENTS

  1. Python 3: UnboundLocalError: local variable referenced before assignment

    File "weird.py", line 5, in main. print f(3) UnboundLocalError: local variable 'f' referenced before assignment. Python sees the f is used as a local variable in [f for f in [1, 2, 3]], and decides that it is also a local variable in f(3). You could add a global f statement: def f(x): return x. def main():

  2. How to Fix

    Output. Hangup (SIGHUP) Traceback (most recent call last): File "Solution.py", line 7, in <module> example_function() File "Solution.py", line 4, in example_function x += 1 # Trying to modify global variable 'x' without declaring it as global UnboundLocalError: local variable 'x' referenced before assignment Solution for Local variable Referenced Before Assignment in Python

  3. UnboundLocalError Local variable Referenced Before Assignment in Python

    Avoid Reassignment of Global Variables. Below, code calculates a new value (local_var) based on the global variable and then prints both the local and global variables separately.It demonstrates that the global variable is accessed directly without being reassigned within the function.

  4. Python UnboundLocalError: local variable referenced before assignment

    UnboundLocalError: local variable referenced before assignment. Example #1: Accessing a Local Variable. Solution #1: Passing Parameters to the Function. Solution #2: Use Global Keyword. Example #2: Function with if-elif statements. Solution #1: Include else statement. Solution #2: Use global keyword. Summary.

  5. Local variable referenced before assignment in Python

    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.

  6. How to fix UnboundLocalError: local variable 'x' referenced before

    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.

  7. [SOLVED] Local Variable Referenced Before Assignment

    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.

  8. Python 3: UnboundLocalError: local variable referenced before assignment

    To fix this, you can either move the assignment of the variable x before the print statement, or give it an initial value before the print statement. def example (): x = 5 print (x) example()

  9. Error Code: UnboundLocalError: local variable referenced before assignment

    Since you don't assign to i until after you modify it, you reference an undefined local variable. Either define i inside the function or use global i to inform Python you wish to act on the global variable by that name.

  10. 【Python】成功解决python报错:UnboundLocalError: local variable 'xxx' referenced

    成功解决python报错:UnboundLocalError: local variable 'xxx' referenced before assignment。在Python中,UnboundLocalError是一种特定的NameError,它会在尝试引用一个还未被赋值的局部变量时发生。Python解释器需要知道变量的类型和作用域,因此,在局部作用域内引用一个未被赋值的变量时,就会抛出这个错误。

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    UnboundLocalError: local variable 'player' referenced before assignment. here's the actual code: if player.cooling_time > 0: player.cooling_time -= 1 Share Sort by: Best. Open comment sort options ... UnboundLocalError: local variable 'player' referenced before assignment Reply reply

  13. python

    1. The variables wins, money and losses were declared outside the scope of the fiftyfifty() function, so you cannot update them from inside the function unless you explicitly declare them as global variables like this: def fiftyfifty(bet): global wins, money, losses. chance = random.randint(0,100)

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    4. Declare global keyword inside your functions to access the global as opposed to local variable. i.e. def dubleIncrement(): global j. j = j+2. def increment(): global i. i = i+1. Note that when you declare i = 0 and j = 0 in your if statement, this is setting a global variable, but since it is outside the scope of any functions, the global ...

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    UnboundLocalError: local variable referenced before assignment issue. 3. Another UnboundLocalError: local variable referenced before assignment Issue. 2. UnBoundLocalError: local variable referenced before assignment (Python) 1. UnboundLocalError: local variable .. referenced before assignment. 2.

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  18. python: UnboundLocalError: local variable 'open' referenced before

    19. This means that further down in your function you create a variable called open: open = ... Rename it so that it doesn't clash with the built-in function. edited May 16, 2012 at 17:02. answered May 16, 2012 at 16:51. NPE. 496k 111 965 1k. "somewhere in your function" here means somewhere after your call to open.

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    UnboundLocalError: local variable 'conn' referenced before assignment [duplicate] Ask Question Asked 12 years, 7 months ago. Modified 1 year, 11 months ago. ... Tkinter program error: UnboundLocalError: local variable 'conn' referenced before assignment. Hot Network Questions