Python shelve簡單資料存放區

Python的shelve模組提供了一種簡單的資料存放區方案，以dict（字典）的形式來操作資料。

#!/usr/bin/pythonimport sys, shelvedef store_person(db):    """    Query user for data and store it in the shelf object    """    pid = raw_input('Enter unique ID number:')    person = {}    person['name'] = raw_input('Enter name:')    person['age'] = raw_input('Enter age:')    person['phone'] = raw_input('Enter phone number:')    db[pid] = persondef lookup_person(db):    """        Query user for ID and desired field, and fetch the corresponding data    from the shelf object    """    pid = raw_input('Enter unique ID number:')    temp = db[pid]    field = raw_input('Please enter name, age or phone:')    field.strip().lower()    print field.capitalize() + ': ', temp[field]def print_help():    print 'The avaliable commands are:'    print 'store    :Stores infomation about a person'    print 'lookup   :Looks up a person form ID number'    print 'quit     :Save changes and exit'    print '?        :Prints this message'def enter_command():    cmd = raw_input('Enter command(? for help):')    cmd = cmd.strip().lower()    return cmddef main():    database = shelve.open('database')  # database stores in current directory    try:        while True:            cmd = enter_command()            if cmd == 'store':                store_person(database)            elif cmd == 'lookup':                lookup_person(database)            elif cmd == '?':                print_help()            elif cmd == 'quit':                return    finally:        database.close()    # Close database in any conditionif __name__ == '__main__':    main()