Raymond Hettinger added the comment: The table is correct. See the interactive session below for confirmation. I think the source of your confusion is that some of the more complex ABCs are able to generate some of the required methods from the ones that are listed (for example, Mapping is able to automatically create __contains__ from __getitem__, so the former is not listed as a required abstract method).

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Container.__abstractmethods__ frozenset({'__contains__'}) Hashable.__abstractmethods__ frozenset({'__hash__'}) Iterable.__abstractmethods__ frozenset({'__iter__'}) Reversible.__abstractmethods__ frozenset({'__reversed__', '__iter__'}) Generator.__abstractmethods__ frozenset({'send', 'throw'}) Sized.__abstractmethods__ frozenset({'__len__'}) Callable.__abstractmethods__ frozenset({'__call__'}) Collection.__abstractmethods__ frozenset({'__iter__', '__len__', '__contains__'}) Sequence.__abstractmethods__ frozenset({'__getitem__', '__len__'}) MutableSequence.__abstractmethods__ frozenset({'insert', '__getitem__', '__len__', '__delitem__', '__setitem__'}) ByteString.__abstractmethods__ frozenset({'__getitem__', '__len__'}) Set.__abstractmethods__ frozenset({'__iter__', '__len__', '__contains__'}) MutableSet.__abstractmethods__ frozenset({'add', '__len__', '__iter__', 'discard', '__contains__'}) Mapping.__abstractmethods__ frozenset({'__getitem__', '__iter__', '__len__'}) MutableMapping.__abstractmethods__ frozenset({'__getitem__', '__len__', '__iter__', '__delitem__', '__setitem__'}) MappingView.__abstractmethods__ frozenset() ItemsView.__abstractmethods__ frozenset() KeysView.__abstractmethods__ frozenset() ValuesView.__abstractmethods__ frozenset() Awaitable.__abstractmethods__ frozenset({'__await__'}) Coroutine.__abstractmethods__ frozenset({'send', 'throw', '__await__'}) AsyncIterable.__abstractmethods__ frozenset({'__aiter__'}) AsyncIterator.__abstractmethods__ frozenset({'__anext__'}) AsyncGenerator.__abstractmethods__ frozenset({'athrow', 'asend'})

---------- resolution: -> not a bug stage: needs patch -> resolved status: open -> closed _______________________________________ Python tracker https://bugs.python.org/issue32621 _______________________________________