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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 unique(self):
 		""" 		Return a Cache which has every element of self, but without 		duplication. Preserve order. Does not hash, so a bit slow. 		"""

		new = self.__class__([])
		for elem in self:
			if elem not in new:
				new.append(elem)
		return new