lbclient.go
func (cc *LBClient) DoDeadline(req *Request, resp *Response, deadline time.Time) error {
	return cc.get().DoDeadline(req, resp, deadline)
}
func (cc *LBClient) DoDeadline(req *Request, resp *Response, deadline time.Time) error {
	return cc.get().DoDeadline(req, resp, deadline)
}
// DoDeadline calls DoDeadline on the least loaded client