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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 FilterRange(self, start_time=None, stop_time=None):
 """Filter the series to lie between start_time and stop_time. Removes all values of the series which are outside of some time range. Args: start_time: If set, timestamps before start_time will be dropped. stop_time: If set, timestamps at or past stop_time will be dropped. """


    start_time = self._NormalizeTime(start_time)
    stop_time = self._NormalizeTime(stop_time)
    self.data = [
        p for p in self.data
        if (start_time is None or p[1] >= start_time) and
        (stop_time is None or p[1] < stop_time)
    ]