133         cls = super().__new__(mcls, name, bases, namespace)
140                 value = getattr(cls, name, None)
143         cls.__abstractmethods__ = frozenset(abstracts)
145         cls._abc_registry = WeakSet()
146         cls._abc_cache = WeakSet()
147         cls._abc_negative_cache = WeakSet()
148         cls._abc_negative_cache_version = ABCMeta._abc_invalidation_counter
149         return cls
151     def register(cls, subclass):  argument
158         if issubclass(subclass, cls):
162         if issubclass(cls, subclass):
165         cls._abc_registry.add(subclass)
169     def _dump_registry(cls, file=None):  argument
171         print("Class: %s.%s" % (cls.__module__, cls.__qualname__), file=file)
173         for name in sorted(cls.__dict__.keys()):
175                 value = getattr(cls, name)
178     def __instancecheck__(cls, instance):  argument
182         if subclass in cls._abc_cache:
186             if (cls._abc_negative_cache_version ==
188                 subclass in cls._abc_negative_cache):
191             return cls.__subclasscheck__(subclass)
192         return any(cls.__subclasscheck__(c) for c in {subclass, subtype})
194     def __subclasscheck__(cls, subclass):  argument
197         if subclass in cls._abc_cache:
200         if cls._abc_negative_cache_version < ABCMeta._abc_invalidation_counter:
202             cls._abc_negative_cache = WeakSet()
203             cls._abc_negative_cache_version = ABCMeta._abc_invalidation_counter
204         elif subclass in cls._abc_negative_cache:
207         ok = cls.__subclasshook__(subclass)
211                 cls._abc_cache.add(subclass)
213                 cls._abc_negative_cache.add(subclass)
216         if cls in getattr(subclass, '__mro__', ()):
217             cls._abc_cache.add(subclass)
220         for rcls in cls._abc_registry:
222                 cls._abc_cache.add(subclass)
225         for scls in cls.__subclasses__():
227                 cls._abc_cache.add(subclass)
230         cls._abc_negative_cache.add(subclass)