对类使用dir()

class A:
    clavariable = 1
    __privilage_variable = 2
    
    def __init__(self):
        instance_variable = 3
    __privilage_instance_variable = 4
    
    def __privilage_instance_method(self):
    pass

print(dir())#对模块
print(dir(A))#对类
a = A()
print(dir(a))#对实例

输出结果

['A', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__']

['_A__privilage_instance_method', '_A__privilage_variable', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'clavariable']

['_A__privilage_instance_method', '_A__privilage_variable', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'clavariable']

dir(实例)

打印
_A__privilage_instance_method#私有实例方法
_A__privilage_variable#私有类属性
clavariable#类变量

不打印
instance_variable = 3 #实例属性
__privilage_instance_variable = 4 #私有实例属性

dir(实例) 和 dir(对象) 结果是一样的
类的属性和方法不管私有或非私有都能打印出来，而实例属性全都不打印