code: async def fetch_batch(self, request):
          
          error_traps = [error_handlers.BatchNotFoundTrap]
  
          batch_id = request.match_info.get('batch_id', '')
          self._validate_id(batch_id)
  
          response = await self._query_validator(
              Message.CLIENT_BATCH_GET_REQUEST,
              client_batch_pb2.ClientBatchGetResponse,
              client_batch_pb2.ClientBatchGetRequest(batch_id=batch_id),
              error_traps)
  
          return self._wrap_response(
              request,
              data=self._expand_batch(response['batch']),
              metadata=self._get_metadata(request, response))
docs: Fetches a specific batch from the validator, specified by id.
  
          Request:
              path:
                  - batch_id: The 128-character id of the batch to be fetched
  
          Response:
              data: A JSON object with the data from the fully expanded Batch
              link: The link to this exact query