isinstance(),issubclass()

isinstance(object,classinfo)

1. 返回True,如果object是classinfo或者classinfo子class的实例。
2. 如果classinfo是包含type和class的tuple，只要满足其中一个的实例，就返回True。
3. object不是实例，返回False。
4. classinfo不是class或者type，触发TypeError。

5. >>> isinstance(2,int)
   True
   >>> isinstance(2,(int,float))
   True
   >>> isinstance(2,[int,float])
   Traceback (most recent call last):
     File "<stdin>", line 1, in <module>
   TypeError: isinstance() arg 2 must be a class, type, or tuple of classes and types

issubclass(class，classinfo)

>>> class a:
...     pass

>>> class b(a):
...     pass

>>> class c(a):
...     pass
...
>>> issubclass(a,a)
True

>>> issubclass(a,b)
False

>>> issubclass(b,a)
True

>>> issubclass(b,[a,c])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: issubclass() arg 2 must be a class or tuple of classes
>>> issubclass(b,(a,c))
True

>>> issubclass(b,(c,a))
True