// NewGroupByScheduler creates a new [GroupByScheduler] from given options.
func NewGroupByScheduler[K comparable, T Task](options GroupBySchedulerOptions[K, T]) *GroupByScheduler[K, T] {
group_by_scheduler.go
return &GroupByScheduler[K, T]{
options: options,
schedulers: make(map[K]RunnableScheduler),
}
}
func (*GroupByScheduler[K, T]) Start() {