code: def test_shape(self, use_lexicon):
      emissions = self._get_emissions()
      decoder = self._get_decoder(use_lexicon=use_lexicon)
  
      results = decoder(emissions)
      self.assertEqual(len(results), emissions.shape[0])
  
imports: import itertools
  import torch
  from parameterized import parameterized
  from torchaudio_unittest.common_utils import get_asset_path, skipIfNoCtcDecoder, TempDirMixin, TorchaudioTestCase
label_desc: Use image node_id 6 for calling the CTCDecoderTest obj's underlying member method code with example usage: obj.test_shape(use_lexicon) without return types