def add_function(a,b): c=a+b print(c) if __name__=="_main_": add_function(2,3)

你的代码有一个小错误。在 `if __name__=="_main_":` 这一行中，`__name__` 应该是双下划线而不是单下划线。正确的写法是 `if __name__ == "__main__":`。这个条件语句的作用是判断当前模块是否作为主程序运行，如果是，则执行 `add_function(2,3)`。请注意修正这个错误并重新运行你的代码。

相关问题

def get_argparser(): parser = argparse.ArgumentParser()

Sorry, as an AI language model, I don't have access to the previous context or the purpose of the function you shared. But based on the function signature, it seems like this is a Python function that returns an instance of the `ArgumentParser` class from the `argparse` module. The purpose of this class is to create a parser object that can parse command-line arguments and options.

Here's an example usage of the `ArgumentParser` class:

import argparse

def get_argparser():
    parser = argparse.ArgumentParser()
    parser.add_argument('--name', help='Enter your name')
    parser.add_argument('--age', type=int, help='Enter your age')
    return parser

if __name__ == '__main__':
    parser = get_argparser()
    args = parser.parse_args()
    print(f"Hello {args.name}, you are {args.age} years old!")

In the above example, the `get_argparser()` function creates an instance of the `ArgumentParser` class and adds two arguments to it - `name` and `age`. The `parse_args()` method of the parser object is then called to parse the command-line arguments and options. Finally, the values of the `name` and `age` arguments are printed using the `print()` function.

if __name__ == '__main__'

This is a Python construct that is often used to allow a module to be both imported and executed as a standalone program.

When a Python module is imported, its code is executed, and any statements that are not inside a function or conditional block are executed immediately. This can be undesirable in some cases, as you may not want the module's code to be executed until you explicitly call a function or method from that module.

To prevent this from happening, you can use the `if __name__ == '__main__'` construct. This code block will only be executed if the module is being run as a standalone program, and not if it is being imported as a module by another program.

For example, consider the following code:

def add(x, y):
    return x + y

if __name__ == '__main__':
    result = add(2, 3)
    print(result)

If you run this code as a standalone program (i.e. by running `python my_module.py`), it will print the result of adding 2 and 3 (which is 5). However, if you import this module into another program, the `result` variable will not be created, and the `print` statement will not be executed. Instead, you can call the `add` function directly from the importing program.