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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 link(self, thing1, thing2):
 		""" 		Link thing1 and thing2, adding the karma of each into 		a single entry. 		If any thing does not exist, it is created. 		"""

		thing1 = thing1.strip().lower()
		thing2 = thing2.strip().lower()
		if thing1 == thing2:
			raise SameName("Attempted to link two of the same name")
		self.change(thing1, 0)
		self.change(thing2, 0)
		return self._link(thing1, thing2)