__name__ value when imported

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Accepted Answer

Python sets __name__ to the module's fully qualified name when a file is imported. For a top-level file named utils.py, that name is 'utils'. For a submodule like mypackage/utils.py imported as 'from mypackage import utils', __name__ would be 'mypackage.utils'. The value '__main__' is reserved for the script that Python runs directly. Knowing this lets you write code that behaves differently depending on whether it is being run or imported - which is exactly what the if __name__ == '__main__' guard relies on.