第17页 Step 2:Storing Records Persistently

这本书是第四版，作者说书中源码都是Python 3.1中调试通过，所以如果你想在Python 2.7.3中调试书本中的很多源码例子都是无法通过的，比如Example1-2的代码，所以需要针对2.7.3的特性进行修改，代码如下：
dbfilename = 'people-file'
ENDDB = 'enddb.'
ENDREC = 'endrec.'
RECSEP = '=>'

def storeDbase(db, dbfilename = dbfilename):
    "formatted dump of database to flat file"
    dbfile = open(dbfilename, 'w')
    for key in db:
        print >> dbfile, key
        for (name, value) in db[key].items():
            print >> dbfile, name + RECSEP + repr(value)
        print >> dbfile, ENDREC
    print >> dbfile, ENDDB
    dbfile.close()

def loadDbase(dbfilename = dbfilename):
    "parse data to reconstruct database"
    dbfile = open(dbfilename)
    import sys
    sys.stdin = dbfile
    db = {}
    key = sys.stdin.readline().strip('\n')
    while key != ENDDB:
        rec = {}
        field = sys.stdin.readline().strip('\n')
        while field != ENDREC:
            name, value = field.split(RECSEP)
            rec[name] = eval(value)
            field = sys.stdin.readline().strip('\n')
        db[key] = rec
        key = sys.stdin.readline().strip('\n')
    dbfile.close()
    return db

if __name__ == '__main__':
    from initdata import db
    storeDbase(db)
    print loadDbase()
上面的代码虽然能在Python 2.7.3中得到想要的结果，但是写法估计还有很多值得改进的地方！