class ChanMACDHistSet():
    def __init__(self, start_time, start_klu, hist_set_dir, pre_histset):
        self.klu_list = []
        self.klu_list.append(start_klu)
        self.ref_klu = None
        self.hist_set_dir = hist_set_dir
        self.next = None
        self.pre = pre_histset
    def set_next(self, next_histset):
        self.next = next_histset
    def add_klu(self, klu):
        self.klu_list.append(klu)
        klu.set_histset(self)