python lession 3 -- module

• define my_module.py

def hello():
    print("hello world!\n")

• import my_module

>>> import my_module
>>> my_module.hello()
hello world!

>>> my_module.__name__
'my_module'

• from my_module import *

>>> from my_module import *
>>> hello()
hello world!

• run module

from my_module import *
if __name__ == "__main__":
    import sys
    hello(sys.argv[1])

def hello(name="world!"):
    print("hello " + name + "!")

• sys.path

>>> import sys
>>> sys.path

dir(): lists the names you have defined currently

>>> import sys
>>> from my_module import *
>>> dir()
['__builtins__', '__doc__', '__name__', '__package__', 'hello', 'sys']

• package:

path/package organize:

first/
    __init__.py  __init__.pyc  second
    hello.py  hello.pyc  __init__.py  __init__.pyc

import package module

import first.second.hello
>>> dir()
['__builtins__', '__doc__', '__name__', '__package__', 'first', 'sys']
>>> first.second.hello.hello()
hello

• __init__.py 

__all__ = ["hello"]

use to import all

 from first.second import *