What if __name__ == '__main__': does

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Accepted Answer

When Python runs a file directly, it sets __name__ to '__main__'. When the same file is imported as a module, __name__ is set to the module's name instead. The guard lets you put test code, a CLI entry point, or setup logic at the bottom of a file without that code firing every time someone imports the module. Every script that might also be imported should have this guard - without it, top-level code runs on import, which is almost never what you want.