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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 update(self, frame_no):
 """ Process the animation effect for the specified frame number. :param frame_no: The index of the frame being generated. """

        if (frame_no >= self._start_frame and
                (self._stop_frame == 0 or frame_no < self._stop_frame)):
            self._update(frame_no)