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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 Element(self, elem, **params):
 """Ensure that the input element is immutable by the transformation. Returns a single element."""

        res = self.__call__(deepcopy(elem), **params)
        if len(res) > 0: 
            return res[0]
        else:
            return None