code: def _parse_single_request_trap_errors(cls, request_data):
          
          try:
              method, params, request_id = cls._parse_single_request(request_data)
              return method, params, request_id, None
          except errors.RPCFault as ex:
              return None, None, ex.request_id, ex
docs: Traps exceptions generated by __parse_single_request and
          converts them into values of request_id and error in the
          returned tuple.
  
          :Returns: (method_name, params_object, request_id, error)
                  Where:
                  - method_name is a str (or None when error is set)
                  - params_object is one of list/tuple/dict/None
                  - request_id is long/int/string/None
                  - error is an instance of errors.RPCFault subclass or None