What Does if name == “main”: Do in Python?
The if __name__ == "main" is a guarding block that is used to contain the code that should only run went the file in which this block is defined is run as a script. What it means is that if you run the file as a script the `__name__variable will be equal to'main'`.
Let’s look at an example:
mylib.py:
def say_hi():
print('hi from the function')
if __name__ == 'main':
print('the main block is being executed')
say_hi()
In the example above, we have defined a say_hi function that will simply say hi when called. Then there is a guarded block with the if __name__ == 'main': statement.
If you run the script in the console lie this:
python3 mylib.py
The output will be the following:
Output:
the main block is being executed
hi from the function
But if you include the mylib.py file in some other python file and run that file as a script, you will see that the guarded block will not be executed.
other.py:
import say_hi from mylib
say_hi()
Output:
hi from the function
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