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What is __name__ == "__main__" in Python?
Python snippets use __name__ == "__main__" checks to ensure that the module-specific code is ran only when they are run directly via Python. Let's see that with an example
If you are a Python beginner, you often see
if __name__ == '__main__'
and get confused about what it does. You are not alone. Most of my students at #PythonToProject Bootcamp struggle with this as well.The
if __name__ == '__main__':
ensures that the snippet under it gets executed only when the file is run directly.# app.py
print ("app.py __name__=", __name__)
if __name__ == '__main__':
print ("inside main check block")
When you run this code
python app.py
you will get the following outputapp.py __name__=__main__
inside main check block
Whereas if you import
app
into another module# temp.py
import app
print ("temp.py __name__=", __name__)
The output will be
app.py __name__=app
temp.py __name__=__main__
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