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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 save(self, *args, **kwargs):
 		""" On save, update timestamps """

		now = datetime.utcnow().replace(tzinfo=pytz.UTC)
		if not self.pk:
			self.created = now
		self.modified = now
		return super(Configuration, self).save(*args, **kwargs)