Comprehensive list of Python protocols/interfaces

Your best reference is always going to be the Python Online Documentation, specifically the section on Special method names.

The interactive Python interpretor is a very useful tool, too. Try some of these:

>>> dir(object)
['__class__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> help(object.__class__)

>>> help(object.__hash__)

>>> help(hash)

By convention, protocols are groups of special methods that describe common behaviors. You can infer protocols from the abstract methods of the collections.abc module (Python 3.3+); see also the docs. Automate this listing with the following:

Given

import abc

import collections as ct

Code

def get_protocols(source=ct.abc):
    """Return a dict of protocols from `collections.abc`."""
    d = {}

    for objname in dir(source):

        if objname.startswith("_"):
            continue
        obj = getattr(source, objname)
        abmethods = sorted(obj.__abstractmethods__)
        if not abmethods:
            continue    
        d[objname] = abmethods        
    return d

Demo

get_protocols()

Output

{
 'AsyncGenerator': ['asend', 'athrow'], 
 'AsyncIterable': ['__aiter__'], 
 'AsyncIterator': ['__anext__'],
 'Awaitable': ['__await__'], 
 'ByteString': ['__getitem__', '__len__'],
 'Callable': ['__call__'], 
 'Collection': ['__contains__', '__iter__', '__len__'], 
 'Container': ['__contains__'], 
 'Coroutine': ['__await__', 'send', 'throw'], 
 'Generator': ['send', 'throw'], 
 'Hashable': ['__hash__'], 
 'Iterable': ['__iter__'], 
 'Iterator': ['__next__'],
 'Mapping': ['__getitem__', '__iter__', '__len__'], 
 'MutableMapping': ['__delitem__', '__getitem__', '__iter__', '__len__', '__setitem__'],
 'MutableSequence': ['__delitem__', '__getitem__', '__len__', '__setitem__', 'insert'], 
 'MutableSet': ['__contains__', '__iter__', '__len__', 'add', 'discard'],
 'Reversible': ['__iter__', '__reversed__'], 
 'Sequence': ['__getitem__', '__len__'], 
 'Set': ['__contains__', '__iter__', '__len__'], 
 'Sized': ['__len__']
}

_{NOTE: When sub-classing, these are (required) abstract methods that do not include the mixin methods. Example: sub-classing collections.abc.Mappings will provide methods .keys(), .values(), .items() (no listed) once the protocol is implemented.}