def _check_pooled_channel_health(self, ch):
        """
        Returns true if the channel has the proper callbacks in pika for delivery.

        We're seeing an issue where channels are considered open and consuming by pika, RabbitMQ,
        and our layer, but the "callbacks" mechanism in pika does not have any entries for
        delivering messages to our layer, therefore messages are being dropped. Rabbit is happily
        sending messages along, resulting in large numbers of UNACKED messages.

        If this method returns false, the channel should be discarded and a new one created.
        """
        cbs = self.client.callbacks._callbacks
        if cbs[ch.get_channel_id()].iterkeys() not in "_on_basic_deliver":
            return False

        return True
dataset/ETHPy150Open ooici/pyon/pyon/net/messaging.py/NodeB._check_pooled_channel_health/swapped operands of `not in`