import collections
import logging

logging.basicConfig(level='INFO')

def super_isinstance(super_inst, cls):
    'Is the cls in the mro after the current class?'
    mro = super_inst.__self__.__class__.__mro__
    thisclass = super_inst.__thisclass__
    return cls in mro and mro.index(thisclass) < mro.index(cls)

class LoggingDict(dict):
    # Simple example of extending a builtin class
    def __setitem__(self, key, value):
        logging.info('Setting %r to %r' % (key, value))
        next_in_mro = super(LoggingDict, self)
        next_in_mro.__setitem__(key, value)

        # Show diagnostics
        print(self.__class__)
        print(super_isinstance(next_in_mro, dict))
        print(super_isinstance(next_in_mro, collections.OrderedDict))
        print(super_isinstance(next_in_mro, LoggingDict))
        print(super_isinstance(next_in_mro, LoggingOD))
        print()

class LoggingOD(LoggingDict, collections.OrderedDict):
    # Build new functionality by reordering the MRO
    pass

if __name__ == '__main__'
    ld = LoggingDict([('red', 1), ('green', 2), ('blue', 3)])
    print(ld)                  # unordered
    ld['red'] = 10

    ld = LoggingOD([('red', 1), ('green', 2), ('blue', 3)])
    print(ld)                  # ordered
    ld['red'] = 10
    print('-' * 20)