IndentationError: unindent does not match any outer indentation level

This error occurs when there is a mismatch in the indentation level of a block of code in Python. For example, if a block of code is indented by 4 spaces, but another block within it is indented by only 2 spaces, this error will occur.

Here's an example of code that would trigger this error:

def my_function():
    if True:
        print("Hello, world!")
    print("Goodbye, world!")

In the above example, the second print statement is not indented at the same level as the first one, causing the error.

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To fix this, you need to make sure that all lines of code within the same block are indented at the same level.

def my_function():
    if True:
        print("Hello, world!")
        print("Goodbye, world!")

This way, the second print statement is indented at the same level as the first one, and the error will be resolved.