1 class Valley:
 2     def __init__(self):
 3         self._name = None
 4 
 5     @property
 6     def name(self):
 7         return self._name
 8 
 9     @name.setter
10     def name(self, val):
11         try:
12             assert val.startswith("g")
13         except  AssertionError:
14             self._name = "g" + val
15         else:
16             self._name = val
17 
18 
19 class SubValley(Valley):
20     @Valley.name.setter
21     def name(self, val):
22         if len(val) >= 3:
23             print(">>长度检查通过")
24         else:
25             raise Exception("{}长度应大于等于3".format(val))
26         super(SubValley, SubValley).name.__set__(self, val)
27 
28 
29 if __name__ == '__main__':
30     obj = SubValley()
31     obj.name = 'lee'
32     print(obj._name)