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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 epochrange(self, epoch=None, starttime=None, endtime=None):
 """ Get epoch range. Returns a list of the record numbers, representing the corresponding starting and ending records within the time range from the epoch data. A None is returned if there is no data either written or found in the time range. """

        return self.varget(variable=epoch, starttime=starttime,
                           endtime=endtime, record_range_only=True)