python json encoder to encode object json with exclusions

jsonencoder.py

class ComplexEncoder(json.JSONEncoder):
    def __init__(self, skipkeys=False, ensure_ascii=True,
                 check_circular=True, allow_nan=True, sort_keys=False,
                 indent=None, separators=None, encoding='utf-8', default=None, excluded=None):
        super(ComplexEncoder, self).__init__(skipkeys, ensure_ascii, check_circular, allow_nan, sort_keys, indent,
                                             separators, encoding, default)
        self.excluded = excluded

    def default(self, obj):
        if hasattr(obj, "__dict__"):
            data = dict([(key, value)
                         for key, value in obj.__dict__.iteritems()
                         if not callable(value) and not key.startswith('_') and key not in self.excluded])
            return data
        # Let the base class default method raise the TypeError
        return json.JSONEncoder.default(self, obj)