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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 revert(self, snapshot: Tuple[Hash32, UUID]) -> None: """ Revert the VM to the state at the snapshot """

        state_root, account_snapshot = snapshot

        # first revert the database state root.
        self._account_db.state_root = state_root
        # now roll the underlying database back
        self._account_db.discard(account_snapshot)