请大家看看这段代码,为什么不能够正常输出呢?
class apple(object): def __init__(self, a): self.a = a print 'apple ...' class bpple(apple): def __init__(self, a, b): super(bpple, self).__init__(a) self.b = b print 'bpple ...' class cpple(apple): def __init__(self, a, c): super(cpple, self).__init__(a) self.c = c print 'cpple ...' class dpple(bpple, cpple): def __init__(self,a, b, c, d): super(dpple, self).__init__(a,b,c) self.d = d print 'dpple ...' d = dpple('a', 'b', 'c', 'd')