Example on understanding "__name__ == '__main__'" in Python.

first_module.py

print("This will always be shown first\n")


def main():
    print("Calling first_module's main method\n")


if __name__ == '__main__':
    # the following will be shown only in `first_module.py`
    main()
    print("== Run directly ==\n")
else:
    # the following will be shown only in `first_module.py`
    print("== Run from import ==\n")


print("Name of the first_module: {}\n".format(__name__))

second_module.py

import first_module

# calling the `main()` function of `first_module`
first_module.main()

# this will only be shown in `second_module.py`
print("Name of the second_module: {}".format(__name__))