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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_period(self, period):

 		"""
 		Set the period for the timestamp. If period is 0 or None, no period
 		will be used.
 		"""

		self._period = period
		if period:
			self._period_seconds = tempora.get_period_seconds(self._period)
			self._date_format = tempora.get_date_format_string(
				self._period_seconds)
		else:
			self._period_seconds = 0
			self._date_format = ''