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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 work_items(self):
 """An iterable of all of WorkItems in the db. This includes both WorkItems with and without results. """

        cur = self._conn.cursor()
        rows = cur.execute("SELECT * FROM work_items")
        for row in rows:
            yield _row_to_work_item(row)