__name__ == "__main__":
The line if __name__ == "__main__": is a common idiom used in Python to check whether the current script is being executed as the main program or if it is being imported as a module.
When a Python module is imported, Python sets the special variable __name__ to the name of the module. However, when a Python script is executed directly as the main program, Python sets __name__ to the string "__main__".
The if __name__ == "__main__": condition checks if the value of__name__ is "__main__", indicating that the current script is being executed as the main program. If the condition is true, the code block inside the if statement is executed.
This idiom is often used to differentiate between code that should only run when the script is executed directly versus code that should only run when the script is imported as a module. It allows you to have code that is specific to the script execution, such as test code, initialization, or command-line interface logic, while preventing that code from running when the script is imported by other scripts.
Here's an example to illustrate the usage:
def my_function():
# Some code here
# Code that should always run
# .....
if __name__ == "__main__":
# Code that runs only when the script is executed directly # ...
In this example, the code inside the my_function() function will always be defined and accessible when the module is imported. However, the code inside the if __name__ == "__main__": block will only execute when the script is run directly, allowing you to have specific behavior for script execution.