clientv3/concurrency/session.go
func WithTTL(ttl int) SessionOption {
	return func(so *sessionOptions) {
		if ttl > 0 {
			so.ttl = ttl
		}
	}
}
func WithTTL(ttl int) SessionOption {
	return func(so *sessionOptions) {
		if ttl > 0 {
			so.ttl = ttl
		}
	}
}
// WithTTL configures the session's TTL in seconds.
// If TTL is <= 0, the default 60 seconds TTL will be used.