python的shelve模块

import shelve
dic1={'pwd':'alex3714','age':18,'sex':'male'}
dic2={'pwd':'alex3715','age':19,'sex':'male'}

d=shelve.open('newdb.txt',writeback=True)
d['egon']={'pwd':'alex3714','age':18,'sex':'male'}#序列化
d['alex']={'pwd':'alex3715','age':19,'sex':'male'}

print(d['egon']['pwd'])  #反序列化
d['egon']['age']=19#要想修改的话必须加上writeback=True
d.close()