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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 copy(self):
 		"""Create a shallow copy of self. 		This runs in O(len(self.num_unique_elements())) 		"""

		out = self._from_iterable(None)
		out._dict = self._dict.copy()
		out._size = self._size
		return out