159
159
# Check if it's a subclass of a registered class (recursive)
160
160
for rcls in cls._abc_registry:
161
161
if issubclass(subclass, rcls):
164
164
# Check if it's a subclass of a subclass (recursive)
165
165
for scls in cls.__subclasses__():
166
166
if issubclass(subclass, scls):
169
169
# No dice; update negative cache
170
170
cls._abc_negative_cache.add(subclass)