':param agent_info: Agent update information.
E.g {"admin_state_up": True}'

def update_agent(self, agent_id, agent_info):

    uri = ('%s/agents/%s' % (self.uri_prefix, agent_id))
    agent = {'agent': agent_info}
    body = jsonutils.dumps(agent)
    (resp, body) = self.put(uri, body)
    self.expected_success(200, resp.status)
    body = jsonutils.loads(body)
    return service_client.ResponseBody(resp, body)
