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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 clear(self):
 """Reset this PeerGroup. This closes all connections to all known peers and forgets about these peers. :returns: A Future that resolves with a value of None when the operation has finished """

        try:
            for peer in self._peers.values():
                peer.close()
        finally:
            self._peers = {}
            self._resetting = False