def unsubscribe(self, queue):
        """Unsubscribe a callback to free object references to enable GC."""
        # note: we can't unsubscribe from the server, so we keep receiving
        # subsequent notifications
        for v in self.subscriptions.values():
            if queue in v:
                v.remove(queue)
Unsubscribe a callback to free object references to enable GC.
electrum/interface.py