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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 frame_to_seconds(self, frame_index, sr):
 """ Return a tuple containing the start and end of the frame in seconds. """

        start_sample, end_sample = self.frame_to_sample(frame_index)
        return sample_to_seconds(start_sample, sampling_rate=sr), sample_to_seconds(end_sample, sampling_rate=sr)