code: def test_in_out(self):  # pylint: disable=no-self-use
      layer = Prenet(128, out_features=[256, 128])
      dummy_input = T.rand(4, 128)
  
      print(layer)
      output = layer(dummy_input)
      assert output.shape[0] == 4
      assert output.shape[1] == 128
  
imports: import unittest
  import torch
  from TTS.tts.layers.tacotron import Prenet, CBHG, Decoder, Encoder
  from TTS.tts.layers.losses import L1LossMasked, SSIMLoss
  from TTS.tts.utils.generic_utils import sequence_mask
label_desc: Use image node_id 1 for calling the PrenetTests obj's underlying member method code with example usage: obj.test_in_out() without return types