Something

class Tag:
    def __init__(self):
        self.length = 0
        self.subTags = []
        self.values = []
    def addTag(self,tag):
        self.subTags.append(tag)
        self.length = len(self.subTags)
    def delTag(self,index):
        del self.subTags[index]
        self.length = len(self.subTags)