Can You Access Global Variables in Python Without the `global` Keyword?

Accessing Global Variables Without 'global' Keyword

In Python, the 'global' keyword is generally used to access or modify global variables within a function's local scope. However, there are scenarios where it may seem like accessing global variables is possible without using 'global'.

To understand this, let's consider the following example:

sub = ['0', '0', '0', '0']

def getJoin():
    return '.'.join(sub)

print(getJoin())

In this code, the 'sub' list is defined outside the 'getJoin()' function, making it a global variable. Surprisingly, accessing 'sub' from within the function works even without explicitly declaring it as 'global'.

The reason for this behavior lies in Python's scoping rules. Unlike some other programming languages, Python allows access to global variables within functions by default. This can be particularly useful in situations where you need to access existing global state without modifying it.

However, it's important to note that accessing global variables without 'global' can have its drawbacks. For instance:

• It can be confusing for other developers reading your code, as it's not clear whether a variable is local or global.
• It can lead to errors if you accidentally assign to a global variable within a function, as Python treats such assignments as the creation of a new local variable.

To avoid these issues, it's recommended to use the 'global' keyword explicitly when accessing or modifying global variables within functions. This ensures clarity and prevents any unexpected behavior due to unintended modifications.

In summary, while Python allows accessing global variables without 'global' by default, it's generally a good practice to use it to avoid potential confusion or errors, especially when modifying global state.

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