新式类和经典类的区别在哪里???

就是在多继承上的顺序问题
py2经典类是按深度优先来继承得，新式类是按广度优先来继承的
py3经典类和新式类都是统一按广度优先来继承的

class People(object):  # 新式类    经典类和新式类在多继承上的方式有所不同
    def __init__(self, name, age):
        self.name = name
        self.age = age
        self.friends = []
        print("---doens't run ")

    def eat(self):
        print("%s is eating..." % self.name)

    def sleep(self):
        print("%s is sleeping..." % self.name)

    def talk(self):
        print("%s is talking..." % self.name)


class Relation(object):
    def __init__(self, n1, n2):
        print("init in relation")

    def make_friends(self, obj):
        print("%s is making friends with %s" % (self.name, obj.name))
        self.friends.append(obj)


class Man(People, Relation):  # 如果两个都有够着函数的话，谁在前面就执行谁的实例化，从左到右。如果其中一个没有，就执行另外一个的构造函数

    def piao(self):
        print("%s is piaoing...20s...done" % self.name)

    def sleep(self):
        People.sleep(self)  # 调用父类的方法，在执行子类的方法，加self就是把自己实例传进去
        print("man is sleeping")


class Women(People, Relation):
    def get_birth(self):
        print("%s is born a baby..." % self.name)


m1 = Man("zhangsan", 8)

# 结果：
# init in relation      当Relation在前面时，就去执行Relation，的实例化参数。class Man(Relation,People)
# ---doens't run        当People在前面时，就去执行People，的实例化参数。class Man(People,Relation)
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再看
D继承BC，BC都继承A。继承的策略叫“广度优先”，就是先把横向的策略都查完，在往上面A查。python3里面都是广度优先。同样的场景（D继承BC，BC继承A，B里面没有初始化函数，C和A里面有初始化函数）在python2里面就是“深度优先。但是如果A继承于（object）新式类的话，”
BC里面都有就按D继承的顺序来

class A:
    def __init__(self):
        print("A")


class B(A):
    def __init__(self):
        print("B")


class C(A):
    def __init__(self):
        print("C")


class D(B, C):
    pass


obj = D()


#结果
# B
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再看
B里面没有就找C

class A:
    def __init__(self):
        print("A")


class B(A):
    pass
    # def __init__(self):
    #     print("B")


class C(A):
    def __init__(self):
        print("C")


class D(B, C):
    pass


obj = D()


#结果
# C
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再看
BC里面都没有就找A

class A:
    def __init__(self):
        print("A")


class B(A):
    pass
    # def __init__(self):
    #     print("B")


class C(A):
    pass
    # def __init__(self):
    #     print("C")


class D(B, C):
    pass


obj = D()


#结果
# A
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