LSTM Data Input #828

Hi, I have made and trained LSTM model with tf.keras, saved it in ONNX format. Later on I want to load and predict the data with ML.NET. But I do not know how to prepare data in 3D format (samples, time_steps, features) as LSTM expected. Does anybody know how to solve this problem?
IDataView dataView = mlContext.Data.LoadFromEnumerable<InputData>(data)
How to define InputData in the right form for LSTM model.