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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 say_tmp_filepath( text = None, preference_program = "festival" ):
 """ Say specified text to a temporary file and return the filepath. """

    filepath = shijian.tmp_filepath() + ".wav"
    say(
        text               = text,
        preference_program = preference_program,
        filepath           = filepath
    )
    return filepath