if __name__=='__main__'
如果当前模块被加载到另一个模块中,if控制的语句就不会被运行,这样可以方便调试
"""
pizza.py
"""
def make_pizza(size):
print("Making a {}-inch pizza.".format(size))
if __name__ == '__main__':
make_pizza(45)
"""
test.py
"""
import pizza
pizza.make_pizza(30)
"""
test文件只会输出Making a 30-inch pizza.
"""
Importing Specific Functions
"""
from module_name import function_name
from module_name import function_0,function_1,function2
"""
from pizza import make_pizza
make_pizza(10)
Importing All Functions
from pizza import *
make_pizza(10)
as
from pizza import make_pizza as mp
mp(10)
import pizza as p
p.make_pizza(10)
Search for Modules
import模组时,编译器首先在内置模组中搜索。如果没有找到,便会在sys.path所存储的路径中寻找。空字符串表示在当前目录下搜索。
import sys
print(sys.path)
Packages
文件夹中必须含有__init__.py文件
"""
两种import方式
"""
import mycompany.pizza
mycompany.pizza.make_pizza(10)
from mycompany import pizza
pizza.make_pizza(10)
Third-party Modules
安装:
pip install module_name
conda install module_name
卸载:
pip uninstall module_name
conda uninstall module_name
常用包
math,numpy,random,you-get,pyinstaller,freegames