code: def speak(self, speech, play_behavior=None):
          # type: (str, PlayBehavior) -> 'ResponseFactory'
          
          ssml = "<speak>{}</speak>".format(self.__trim_outputspeech(
              speech_output=speech))
          self.response.output_speech = SsmlOutputSpeech(
              ssml=ssml, play_behavior=play_behavior)
          return self
docs: Say the provided speech to the user.
  
          :param speech: the output speech sent back to the user.
          :type speech: str
          :param play_behavior: attribute to control alexa's speech
              interruption
          :type play_behavior: ask_sdk_model.ui.play_behavior.PlayBehavior
          :return: response factory with partial response being built and
              access from self.response.
          :rtype: ResponseFactory