Python导入包注意事项

>>> import folder1
>>> folder1.abcd.b
Traceback (most recent call last):  
File "<stdin>", line 1, in <module>
AttributeError: module 'folder1' has no attribute 'abcd'
>>> from folder1 import abcd
>>> bob = abcd.Myclass(name = 'Bob', age = 20)
>>> bob.name
'Bob'
>>> bob.get_info()my name is Bob and age is 20
>>> from folder1.abcd import b
>>> b
2
>>> import folder1.abcd
>>> abcd.bTraceback (most recent call last):  File "<stdin>", line 1, in <module>NameError: name 'abcd' is not defined
>>> folder1.abcd.b2
>>> import folder1.abcd as aa
>>> aa.b
2