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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def speak(self, speech, play_behavior=None):
 # type: (str, PlayBehavior) -> 'ResponseFactory' """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 """

        ssml = "<speak>{}</speak>".format(self.__trim_outputspeech(
            speech_output=speech))
        self.response.output_speech = SsmlOutputSpeech(
            ssml=ssml, play_behavior=play_behavior)
        return self