new_contents: import unittest
  from unittest import mock
  
  from mycroft.tts.espeak_tts import ESpeak
  
  
  @mock.patch('mycroft.tts.tts.PlaybackThread')
  class TestMimic(unittest.TestCase):
      @mock.patch('mycroft.tts.espeak_tts.subprocess')
      def test_get_tts(self, mock_subprocess, _):
          conf = {
              "lang": "english-us",
              "voice": "m1"
          }
          e = ESpeak('en-US', conf)
          sentence = 'hello'
          wav_filename = 'abc.wav'
          wav, phonemes = e.get_tts(sentence, wav_filename)
          self.assertTrue(phonemes is None)
          mock_subprocess.call.called_with(['espeak', '-v',
                                            conf['lang'] + '+' + conf['voice'],
                                            '-w', wav_filename,
                                            sentence])
  
subject: Add basic unittest for espeak