'Method used to get the status of the listener resource.
This method is used to get the status of the listener
resources belonged to the specific Load Balancer.
:param loadbalancer_id: The ID of the Load Balancer.
:returns: The status dictionary of the listener
resource. The key is the ID of the listener resource. The
value is the operating status of the listener resource.'

def _get_listener_status(self, loadbalancer_id):

    resp = self._retrieve_loadbalancer_status_tree(loadbalancer_id)
    status_tree = resp.get('statuses').get('loadbalancer')
    status_dict = dict()
    listeners_status = status_tree.get('listeners')
    for listener_status in listeners_status:
        key = listener_status.get('id')
        if (key is None):
            continue
        value = listener_status.get('operating_status')
        status_dict[key] = value
    return status_dict
