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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 descendants(self):
 """Recursively return every dataset below current item."""

        for i in self.current_item.items:
            self.move_to(i)
            if i.type == TYPE_COLLECTION:
                for c in self.children:
                    yield c
            else:
                yield i
            self.move_up()