abstractmethod is not defined

I cannot run this code, because I get the exception:

NameError: name 'abstractmethod' is not defined
File "C:\Tests\trunk\PythonTests\AbstractClasses.py", line 12, in <module>
  class MyIterable:
File "C:\Tests\trunk\PythonTests\AbstractClasses.py", line 15, in MyIterable
  @abstractmethod

from abc import ABCMeta

class Foo(obj开发者_JAVA技巧ect):
    def __getitem__(self, index):
        print '__get_item__ Foo'
    def __len__(self):
        print '__len__ Foo'
    def get_iterator(self):
        print 'get_iterator Foo'
        return iter(self)

class MyIterable:
    __metaclass__ = ABCMeta

    @abstractmethod
    def __iter__(self):
        while False:
            yield None

    def get_iterator(self):
        return self.__iter__()

    @classmethod
    def __subclasshook__(cls, C):
        if cls is MyIterable:
            if any("__iter__" in B.__dict__ for B in C.__mro__):
                print "I'm in __subclasshook__"
                return True
        return NotImplemented

MyIterable.register(Foo)

x=Foo()
x.__subclasshook__()

I'm sure that code is ok, because I got it from http://docs.python.org/library/abc.html

EDIT

Thanks for answer, it works now, but why

print '__subclasshook__'

this doesn't work ? I don't get in Debug I/0

You only imported ABCMeta

from abc import ABCMeta

Also import abstractmethod

from abc import ABCMeta, abstractmethod

and everything should be fine.

You need to import abstractmethod from abc. abc is the inbuilt Python package for Abstract Base Classes.

An example:

from abc import abstractmethod

class Foo:
    def __init():
        pass
    
    @abstractmethod
    def bar():
        pass

You need to change import ABC to ABCMeta

from abc import ABCMeta, abstractmethod

class AbstractClassExample(ABCMeta):

    def __init__(self, value):
        self.value = value
        super().__init__()

    @abstractmethod
    def do_something(self):
        print("do_something")


class DoAdd42(AbstractClassExample):
    print("DoAdd42")

x = DoAdd42(4)