code: async def fetch_transaction(self, request):
          
          error_traps = [error_handlers.TransactionNotFoundTrap]
  
          txn_id = request.match_info.get('transaction_id', '')
          self._validate_id(txn_id)
  
          response = await self._query_validator(
              Message.CLIENT_TRANSACTION_GET_REQUEST,
              client_transaction_pb2.ClientTransactionGetResponse,
              client_transaction_pb2.ClientTransactionGetRequest(
                  transaction_id=txn_id),
              error_traps)
  
          return self._wrap_response(
              request,
              data=self._expand_transaction(response['transaction']),
              metadata=self._get_metadata(request, response))
docs: Fetches a specific transaction from the validator, specified by id.
  
          Request:
              path:
                  - transaction_id: The 128-character id of the txn to be fetched
  
          Response:
              data: A JSON object with the data from the expanded Transaction
              link: The link to this exact query