What does 'if __name__ == "__main__"' do?

The expression if __name__ == "__main__": is used in Python scripts to determine whether a script is being run as the main program or if it is being imported as a module in another script. When a Python file is executed directly, Python assigns the string "__main__" to the special variable __name__. If the file is being imported, __name__ will contain the name of the module instead.

This conditional statement allows you to control the execution of code, ensuring that certain parts only run when the script is being executed directly.

Here's a simple example:

def main(): print("This script is running directly.") if __name__ == "__main__": main()

Python if __name__ == "__main__" main program script execution module import

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