1.
What's the input dimensionality of this layer?(How many columns/features does the input data set have)
Model.add(LSTM(42,input_shape=(23,5),return_sequences=True))
2. How many LSTM cells does this layer have?
Model.add(LSTM(42,input_shape=(23,5),return_sequences=True))
3. How many future time steps does this layer predict?
(Note: this depends on the number of time-steps this layer received as input. Since Keras only supports symetrical input/output lenghts the input length determines the output length)
Model.add(LSTM(42,input_shape=(23,5),return_sequences=True))