Can Python Functions Access and Modify the Same Global Variable, and Does Calling Order Matter?

Can Python Functions Access Global Variables?

In Python, global variables should be used cautiously to avoid confusion. However, when unavoidable, it's crucial to determine if the following approach is valid for utilizing them:

x = "somevalue"

def func_A():
    global x
    # Modify x

def func_B():
    x = func_A()
    # Use modified x

Does func_B have access to the same modified global x used in func_A? And does the order of function calls matter?

Understanding Global Variables in Python Functions

To change the value of a global variable within a function, the global keyword must be used:

global some_var
some_var = 55

This modifies the global variable some_var, whereas assigning a value without global would create a local variable within the function.

In the provided code, func_B can indeed access the same modified global x used in func_A. When func_B is called, it first retrieves the modified x from func_A. Therefore, func_B uses the global x with the updated value.

Regarding the order of function calls, it does matter. In this case, func_A must be called before func_B because func_B relies on the modified x provided by func_A. However, in general, the order of function definitions doesn't affect their behavior unless they refer to each other.

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