I would like to create a simple Keras neural network that accepts an input matrix of dimension (rows, columns) = (n, m), flattens the matrix to a dimension (n*m, 1), sends the flattened matrix through a number of arbitrary layers, and in the final layer, once more unflattens the matrix to a dimension of (n, m) before releasing this final matrix as an output.
The issue I'm having is that I haven't found any documentation for an Unflatten layer at the keras.io page, and I'm wondering whether there is a reason that such a seemingly standard common use layer doesn't exist. Is there a much more natural and easy way to do what I'm proposing?