in tts/src/tts/synthesizer.py [0:0]
def __init__(self, engine='POLLY_SERVICE', polly_service_name='polly'):
if engine not in self.ENGINES:
msg = 'bad engine {} which is not one of {}'.format(engine, ', '.join(SpeechSynthesizer.ENGINES.keys()))
raise SpeechSynthesizer.BadEngineError(msg)
engine_kwargs = {'polly_service_name': polly_service_name} if engine == 'POLLY_SERVICE' else {}
self.engine = self.ENGINES[engine](**engine_kwargs)
self.default_text_type = 'text'
self.default_voice_id = 'Joanna'
self.default_output_format = 'ogg_vorbis'