<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_extra_info(self, name, default=None):
 """ Return optional transport information. - `'related_address'`: the related address - `'sockname'`: the relayed address """

        if name == 'related_address':
            return self.__inner_protocol.transport.get_extra_info('sockname')
        elif name == 'sockname':
            return self.__relayed_address
        return default