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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.

Running Python module

# 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 output
app.py __name__=__main__
inside main check block

Importing Python module

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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