python类属性在继承中的修改的影响

 class A(object):
     x = 1

 class B(A):
     pass

 class C(A):
     pass

 # 通过父类修改类属性,子类继承的类属性也改变
 A.x = 3
 print(A.x, B.x, C.x)
 # 通过子类修改继承自父类的类属性,只会改变该子类继承的类属性
 B.x = 2
 print(A.x, B.x, C.x)
 # 子类先修改继承的类属性,父类再修改类属性,将不会再对已经修改过的子类类属性做出改变
 B.x = 4
 A.x = 1
 print(A.x, B.x, C.x)