query.go
func (q *Query) WaitTimeout(d time.Duration) *Query {
	q.headers = append(q.headers, fmt.Sprintf("WaitTimeout: %d", d/time.Millisecond))
	return q
}
func (q *Query) WaitTimeout(d time.Duration) *Query {
	q.headers = append(q.headers, fmt.Sprintf("WaitTimeout: %d", d/time.Millisecond))
	return q
}
// WaitTimeout sets the upper limit on the time to wait before executing the query.