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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 _reatach(self):
 """Reinsert the hidden items."""

        for item, p, idx in self._detached:
            # The item may have been deleted.
            if self.treeview.exists(item) and self.treeview.exists(p):
                self.treeview.move(item, p, idx)
        self._detached = []