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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 effective_FPS(self):
 """ Calculates the effective frames-per-second - this should largely correlate to the desired FPS supplied in the constructor, but no guarantees are given. :returns: The effective frame rate. :rtype: float """

        if self.start_time is None:
            self.start_time = 0
        elapsed = monotonic() - self.start_time
        return self.called / elapsed