code: func (t *MockTransactor) SendTransactionProposal(proposal *fab.TransactionProposal, targets []fab.ProposalProcessor) ([]*fab.TransactionProposalResponse, error) {
  	rqtx, cancel := contextImpl.NewRequest(t.Ctx, contextImpl.WithTimeout(10*time.Second))
  	defer cancel()
  	return txn.SendProposal(rqtx, proposal, targets)
  }
docs: // SendTransactionProposal sends a TransactionProposal to the target peers.