code: func (t *MockTransactor) CreateTransaction(request fab.TransactionRequest) (*fab.Transaction, error) {
  	response := &fab.Transaction{
  		Proposal: &fab.TransactionProposal{
  			Proposal: &pb.Proposal{},
  		},
  		Transaction: &pb.Transaction{},
  	}
  	return response, nil
  }
docs: // CreateTransaction create a transaction with proposal response.