public async stt::Task MutateRow1Async()
        {
            moq::Mock <Bigtable.BigtableClient> mockGrpcClient = new moq::Mock <Bigtable.BigtableClient>(moq::MockBehavior.Strict);
            MutateRowRequest request = new MutateRowRequest
            {
                TableNameAsTableName = TableName.FromProjectInstanceTable("[PROJECT]", "[INSTANCE]", "[TABLE]"),
                RowKey    = proto::ByteString.CopyFromUtf8("row_key7adfb7cb"),
                Mutations = { new Mutation(), },
            };
            MutateRowResponse expectedResponse = new MutateRowResponse {
            };

            mockGrpcClient.Setup(x => x.MutateRowAsync(request, moq::It.IsAny <grpccore::CallOptions>())).Returns(new grpccore::AsyncUnaryCall <MutateRowResponse>(stt::Task.FromResult(expectedResponse), null, null, null, null));
            BigtableClient    client = new BigtableClientImpl(mockGrpcClient.Object, null);
            MutateRowResponse responseCallSettings = await client.MutateRowAsync(request.TableName, request.RowKey, request.Mutations, gaxgrpc::CallSettings.FromCancellationToken(st::CancellationToken.None));

            xunit::Assert.Same(expectedResponse, responseCallSettings);
            MutateRowResponse responseCancellationToken = await client.MutateRowAsync(request.TableName, request.RowKey, request.Mutations, st::CancellationToken.None);

            xunit::Assert.Same(expectedResponse, responseCancellationToken);
            mockGrpcClient.VerifyAll();
        }