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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 retrieve_by_id(self, id_):
 """Return a JSSObject for the element with ID id_"""

        items_with_id = [item for item in self if item.id == int(id_)]
        if len(items_with_id) == 1:
            return items_with_id[0].retrieve()