import test
'''使用test字符串作为名字来寻找model,
寻找顺序 缓存 > builtinmodel > sys.ptah(按顺序),一旦找到就停止寻找
找到后在单独的命名空间中运行 (load)
最后赋值给tetst
'''
print(test) #<module 'test' from 'F:\\python\\pyEasyFile\\test.py'>

import test as t
print(test) #NameError: name 'test' is not defined
print(t)    #<module 'test' from 'F:\\python\\pyEasyFile\\test.py'>

from test import A
print(A)   #<class 'test.A'>

from test import A as myA
print(myA) #<class 'test.A'>

import mypackage
#执行__init__.py中的代码
print(mypackage.B)     #<class 'mypackage.B'>
print(dir(mypackage))  #['B', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__']

# 除了__init__其余不会引入

class B:
    pass

import mypackage.mymodel
#赋值mypackage变量为package
#添加一个属性mymodel

print(mypackage.mymodel)  #<module 'mypackage.mymodel' from 'F:\\python\\pyEasyFile\\mypackage\\mymodel.py'>
print(mypackage) #<module 'mypackage' from 'F:\\python\\pyEasyFile\\mypackage\\__init__.py'>
print(dir(mypackage)) #['B', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__', 'mymodel']

import mypackage.mymodel as Mymd
print(Mymd)      #<module 'mypackage.mymodel' from 'F:\\python\\pyEasyFile\\mypackage\\mymodel.py'>
print(mypackage) #NameError: name 'mypackage' is not defined

# absolute import
from mypackage.util import f

# relative import (同一层级)
from .util import f