python 包(模块 函数 类 定义 导入)使用详解

my_package/
    __init__.py
    module1.py
    module2.py

# my_package/module1.py
def hello():
    print("Hello from module 1!")

# my_package/module2.py
class MyClass:
    def __init__(self):
        print("Hello from MyClass!")

# my_package/__init__.py
from .module1 import hello
from .module2 import MyClass

# my_package/__init__.py
VERSioN = '1.0.0'
print("Initializing my_package...")

import my_package
# 调用函数
my_package.hello()       # 输出 "Hello from module 1!"
# 创建类实例
obj = my_package.MyClass()
# 输出 "Hello from MyClass!"

from my_package.module1 import hello
hello()   # 输出 "Hello from module 1!"