Python ImportError: cannot import name ABC

Python 3.5.2 测试可以运行

import sys
from abc import ABC,abstractmethod                                              

class MyBase(ABC):
    @abstractmethod
    def func(self):
        '''Implement in subclass'''                                             

class MyClass(MyBase):
    def func(self):
        con = "%s %s" % (self.__class__.__name__,sys._getframe().f_code.co_name)
        print(con)                                                              

obj = MyClass()
obj.func()

输出

MyClass func

python 2.7.12测试可以运行

import sys
from abc import ABCMeta, abstractmethod                                         

class MyBase():
    __metaclass__ = ABCMeta
    @abstractmethod
    def func(self):
        '''Implement in subclass'''                                             

class MyClass(MyBase):
    def func(self):
        con = "%s %s" % (self.__class__.__name__,sys._getframe().f_code.co_name)
        print(con)                                                              

obj = MyClass()
obj.func()

输出

MyClass func

上面python2的代码在python3中也可以正常输出.

还有一种3.0-3.3的写法 不写了.

兼容后的代码

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function                                           

import sys
if sys.version > '3':
    from abc import ABC,abstractmethod
else:
    from abc import ABCMeta, abstractmethod                                     

if sys.version > '3':
    class MyBase(ABC):
        @abstractmethod
        def func(self):
            '''Implement in subclass'''
else:
    class MyBase():
        __metaclass__ = ABCMeta
        @abstractmethod
        def func(self):
            '''Implement in subclass'''                                         

class MyClass(MyBase):
    def func(self):
        con = "%s %s" % (self.__class__.__name__,sys._getframe().f_code.co_name)
        print(con)                                                              

obj = MyClass()
obj.func()