1.作用：存储

2.创建方法  Person类及Manager类
from person import Person,Manager
bob = Person('bob smith')
sue = Person('Sue Jones',job = 'dev',pay = 100000)
tom  = Manager('Tom Jones',50000)


import shelve
db = shelve.open('persondb')
for dbject in (bob,sue,tom):
    db[dbject.name] = dbject

db.close()

3.查看存储的内容

>>> import shelve
>>> db = shelve.open('persondb')
>>> len(db)
3
>>> list(db.keys())
['bob smith', 'Sue Jones', 'Tom Jones']
>>> bob = db['bob smith']
>>> print(bob)
[Persion:bob smith,0]
>>> for key in db:
print(key,"=>",db[key])
bob smith => [Persion:bob smith,0]
Sue Jones => [Persion:Sue Jones,100000]
Tom Jones => [Persion:Tom Jones,50000]
>>> for key in sorted(db):
print(key,"=>",db[key])
Sue Jones => [Persion:Sue Jones,100000]
Tom Jones => [Persion:Tom Jones,50000]
bob smith => [Persion:bob smith,0]

4.更新数据

import shelve
db = shelve.open('persondb')


for key in sorted(db):
    print(key,"=>",db[key])


sue  = db['Sue Jones']
sue.giveRaise(.10)
db['Sue Jones'] = sue
db.close()