'Unbind a queue from an exchange with a given bind key.
Unbind a queue specified by name, from an exchange specified by
name, that is already bound with a bind key. The queue and
exchange must already exist on the broker, and bound with the bind
key for the operation to complete successfully. Queues may be
bound to exchanges multiple times with different keys, thus the
bind key is a required field to unbind in an explicit way.
:param queue: The name of the queue to be unbound.
:type queue: str
:param exchange: The name of the exchange that the queue should be
unbound from.
:type exchange: str
:param routing_key: The existing bind key between the specified
queue and a specified exchange that should be unbound.
:type routing_key: str'

def queue_unbind(self, queue, exchange, routing_key, **kwargs):

    self._broker.unbind(exchange, queue, routing_key)
