How to do modular programming in Python?

In Python, modular programming refers to breaking down a program into multiple independent modules, each with its own functionality and responsibility, and can be developed, tested, and maintained independently. This can improve code readability, maintainability, and reusability.

To do modular programming, you can follow the steps below:

1. Creating Modules: Encapsulate related functions, variables, or classes into a standalone .py file, known as a module. A module can contain multiple functions, classes, or variables.
2. Import Modules: In another .py file, use the import statement to import the necessary module. Once a module is imported, you can then use the functions, classes, or variables defined within that module.
3. Using modules: call the imported functions or classes in the main program to achieve the program’s functionality.

For example, a function add(a, b) is defined in a module called utils.py, which can be imported into another .py file and the add function can be called.

# utils.py
def add(a, b):
    return a + b

# main.py
import utils

result = utils.add(2, 3)
print(result)  # 输出5

By using modular programming, you can break down a program into various modules, making the code more clear and easier to maintain. Additionally, modular programming can also improve code reusability, as multiple modules can be called upon to reuse code effectively.