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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 deserialize_iter(self, attr, iter_type):
 """Deserialize an iterable. :param list attr: Iterable to be deserialized. :param str iter_type: The type of object in the iterable. :rtype: list """

        if attr is None:
            return None
        if isinstance(attr, ET.Element): # If I receive an element here, get the children
            attr = list(attr)
        if not isinstance(attr, (list, set)):
            raise DeserializationError("Cannot deserialize as [{}] an object of type {}".format(
                iter_type,
                type(attr)
            ))
        return [self.deserialize_data(a, iter_type) for a in attr]