public async Task DeleteAllContextsAsync2()
        {
            Mock <Contexts.ContextsClient> mockGrpcClient = new Mock <Contexts.ContextsClient>(MockBehavior.Strict);
            DeleteAllContextsRequest       request        = new DeleteAllContextsRequest
            {
                ParentAsSessionName = new SessionName("[PROJECT]", "[SESSION]"),
            };
            Empty expectedResponse = new Empty();

            mockGrpcClient.Setup(x => x.DeleteAllContextsAsync(request, It.IsAny <CallOptions>()))
            .Returns(new Grpc.Core.AsyncUnaryCall <Empty>(Task.FromResult(expectedResponse), null, null, null, null));
            ContextsClient client = new ContextsClientImpl(mockGrpcClient.Object, null);
            await client.DeleteAllContextsAsync(request);

            mockGrpcClient.VerifyAll();
        }