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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 deactivate(self, address):
 """ Deactivate an address from the connection pool, if present, closing all idle connection to that address """

        with self.lock:
            try:
                connections = self.connections[address]
            except KeyError: # already removed from the connection pool
                return
            for conn in list(connections):
                if not conn.in_use:
                    connections.remove(conn)
                    try:
                        conn.close()
                    except IOError:
                        pass
            if not connections:
                self.remove(address)