code: def test_Encoder_invalid_type():
      with pytest.raises(ValueError):
          TransformerEncoder(20, input_layer="fff")
  
imports: import pytest
  import torch
  from espnet2.asr.ctc import CTC
  from espnet2.asr.encoder.transformer_encoder import TransformerEncoder
label_desc: Use image node_id 4 for calling a global function with example usage: test_Encoder_invalid_type() without return types