Loads the images and latent values into Numpy arrays.

def _load_data(filepath):
  """Loads the images and latent values into Numpy arrays."""
  with h5py.File(filepath, "r") as h5dataset:
    image_array = np.array(h5dataset["images"])
    # The 'label' data set in the hdf5 file actually contains the float values
    # and not the class labels.
    values_array = np.array(h5dataset["labels"])
  return image_array, values_array