'Update the WorkerChannelInstance
:param unicode capacity: The capacity
:param bool available: The available
:returns: Updated WorkerChannelInstance
:rtype: twilio.rest.taskrouter.v1.workspace.worker.worker_channel.WorkerChannelInstance'

def update(self, capacity=values.unset, available=values.unset):

    data = values.of({'Capacity': capacity, 'Available': available})
    payload = self._version.update('POST', self._uri, data=data)
    return WorkerChannelInstance(self._version, payload, workspace_sid=self._solution['workspace_sid'], worker_sid=self._solution['worker_sid'], sid=self._solution['sid'])
