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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 set_epochrange(self, start_epoch, stop_epoch, step_size):
 """Set a range of epochs, all times are UT :param start_epoch: str; start epoch of the format 'YYYY-MM-DD [HH-MM-SS]' :param stop_epoch: str; final epoch of the format 'YYYY-MM-DD [HH-MM-SS]' :param step_size: str; :return: None Note that dates are mandatory; if no time is given, midnight is assumed. """

        self.start_epoch = start_epoch
        self.stop_epoch = stop_epoch
        self.step_size = step_size

        return None