code: def get_filename(self, t):
  		
  		root, ext = os.path.splitext(self.base_filename)
  		# remove seconds not significant to the period
  		if self._period_seconds:
  			t -= t % self._period_seconds
  		# convert it to a datetime object for formatting
  		dt = datetime.datetime.utcfromtimestamp(t)
  		# append the datestring to the filename
  		# workaround for datetime.strftime not handling '' properly
  		appended_date = (
  			dt.strftime(self._date_format)
  			if self._date_format != '' else ''
  		)
  		if appended_date:
  			# in the future, it would be nice for this format
  			#  to be supplied as a parameter.
  			result = root + ' ' + appended_date + ext
  		else:
  			result = self.base_filename
  		return result
docs: Return the appropriate filename for the given time
  		based on the defined period.