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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 get_toplevel_parent(self, treeitem):
 """Returns the top level parent for treeitem."""

        tv = self.treeview
        toplevel_items = tv.get_children()

        item = treeitem
        while not (item in toplevel_items):
            item = tv.parent(item)

        return item