<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def error_name(self) :
        "the error name for a DBUS.MESSAGE_TYPE_ERROR message."
        result = dbus.dbus_message_get_error_name(self._dbobj)
        if result != None :
            result = result.decode()
        #end if
        return \
            result