模块 Modules

dog.py

def bark():
    print("woof!")

main.py

import dog
from dog import bark

dog.bark() # "woof!"
bark() # "woof!"

Create lib folder

__init__.py (nothing here, just to delcare the lib is a module in python)

dog.py

def bark():
    print("woof!")

main.py

from lib import dog
from lib.dog import bark

dog.bark() # "woof!"
bark() # "woof!"

Buit-in modules

• math for math utilities
• re for regular expressions
• json to work with JSON datetime to work with dates sqlite to use SQLite
• os for Operating System utilities
• random for random number generation
• statistics for statistics utilities requests to perform HTTP network requests
• http to create HTTP servers
• urllib to manage URLS

import math
from math import sqrt

math.sqrt(4) # 2.0
sqrt(4) # 2.0