code: func OutcomeFromRPCError(err error) UpdateOutcome {
  	if err == nil {
  		return OutcomeUpdateSuccess
  	}
  	if details, ok := err.(client.RPCError); ok {
  		if details.GrpcCode != codes.OK {
  			return UpdateOutcome(fmt.Sprintf("GRPC_ERROR_%d", details.GrpcCode))
  		}
  		return UpdateOutcome(fmt.Sprintf("MINT_TOKEN_ERROR_%s", details.ErrorCode))
  	}
  	return OutcomeUnknownRPCError
  }
docs: // OutcomeFromRPCError transform MintToken error into an update outcome.