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Yoon Choi
1,649 PointsWhy don't you have an explanation for dunder name and dunder main?
Can we have a discussion on what name and main is?
1 Answer

Chris Freeman
Treehouse Moderator 68,460 PointsGood question! As answered here and here,
This is a common python idiom to detect if a module is imported or being executed directly.
When a python module is imported into another module, its __name__
attribute is set to be the same as the module name. When a python module is executed, the top level module attribute __name__
is changed to be "__main__
". This way a module can tell the difference between if it is being imported or executed.
The python idiom
if __name__ == "__main__":
main()
says, "if my __name__
attribute has been changed to the string "__main__
", then execute the function main()
. The "pass
" would be replaced with the code to be executed.
Post back if you have more questions. Good luck!!