def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def message_data(self):
        if self.proto_view == 0:
            return self.message.plain_bits_str
        elif self.proto_view == 1:
            return self.message.plain_hex_str
        elif self.proto_view == 2:
            return self.message.plain_ascii_str
        else:
            return None