isinstance and issubclass

isinstance

class A(object):
    pass
 
obj = A()
 
isinstance(obj, A)
#检查obj对象是否是A类的对象

　　

 issubclass

class A(object):
    pass
 
class B(A):
    pass
 
issubclass(B, A)
#检查B类是否，是A类的子类