backtrader_源码学习_findbases函数用于发现两个类之间有多少继承的类

# 从当前类出发到top类，中间有多少继承的类
def findbases(kls, topclass):
    retval = list()
    for base in kls.__bases__:
        if issubclass(base, topclass):
            retval.extend(findbases(base, topclass))
            retval.append(base)
    # return list(set(retval)) # 觉得用set去除重复可能比较好
    return retval

class People(object):
    def __init__(self):
        self.head_number=1
        self.hand_number=2
        self.foot_number=2
        self.eye_number=2
        self.nose_number=1
    def get_head_numer(self):
        return self.head_numer
    def get_hand_number(self):
        return self.hand_number
    def get_foot_number(self):
        return self.foot_number
    def get_eye_number(self):
        return self.eye_number
    def get_nose_number(self):
        return self.nose_number 
    def can_act(self):
        print("people can eat")
        print("people can smile")
        print("people can speak")
class Teacher(People):
    def __init__(self):
        super(Teacher,self).__init__()
    def can_act(self):
        print("teacher can teach")
class Student(People):
    def __init__(self):
        super(Student,self).__init__()
    def can_act(self):
        print("sudent is learning****")
class Son(Student):
    def __init__(self):
        super(Son,self).__init__()
    def can_act(self):
        print(" son can learn from parents")
class GrandSon(Son,Student,Teacher):
    def __init__(self):
        super(GrandSon,self).__init__()
    def can_act(self):
        print(" GrandSon can learn from parents")