在一些特定场合，需要动态创建类，比如创建表单，就会用到type动态创建类，举个例子：
1 class Person(object):
2
3 def __init__(self,name,age):
4 self.name = name
5 self.age = age
6
7
8 p = Person("aiden",22)
9 print(type(p))
10 print(type(Person))
11
12
13
14 def __init__(self,name,age):
15 self.name = name
16 self.age = age
17
18 dog_class = type("Dog",(object,),{"role":"dog","__init__":__init__}) #动态添加属性与方法
19 print(dog_class)
20
21 d = dog_class('mjj',22)
22 print(d.role,d.name,d.age)