python面向对象法实现图书管理系统

class Book(object): def __init__(self, name, author, status, bookindex):  self.name = name  self.author = author  self.status = status  self.bookindex = bookindex def __str__(self):  if self.status == 1:   stats = '未借出'  elif self.status == 0:   stats = '已借出'  else:   stats = '状态异常'  return '书名: 《%s》 作者: %s 状态: <%s> 位置: %s' /    % (self.name, self.author, stats, self.bookindex)class BookManage(object): books = [] def start(self):  self.books.append(Book('python', 'guido', 1, 'ISO9001'))  self.books.append(Book('c', '谭浩强', 1, 'NFS8102'))  self.books.append(Book('java', 'westos', 1, 'PKA7844'))  # 0:借出 1：存在  # python 1  # c 1  # java 1 def Menu(self):  self.start()  while True:   print("""      图书管理系统  1.查询图书  2.增加图书  3.借阅图书  4.归还图书  5.退出系统  """)   choice = input('请选择：')   if choice == '1':    self.showAllBook()   elif choice == '2':    self.addBook()   elif choice == '3':    self.borrowBook()   elif choice == '4':    self.returnBook()   elif choice == '5':    print('欢迎下次使用...')    exit()   else:    print('请输入正确选择')    continue def showAllBook(self):  for book in self.books:   print(book) def addBook(self):  name = input('图书名称:')  self.books.append(Book(name, input('作者:'), 1, input('存储位置:')))  print('图书《%s》增加成功' % name) def checkBook(self, name):  for book in self.books:   if book.name == name:    return book  else:   return None def borrowBook(self):  name = input('借阅图书名称: ')  ret = self.checkBook(name)  print(ret)  if ret != None:   if ret.status == 0:    print('书籍《%s》已经借出' % name)   else:    ret.status = 0    print('书籍《%s》借阅成功' % name)  else:   print('书籍《%s》不存在' % name) def returnBook(self):  name = input('归还图书名称:')  ret = self.checkBook(name)  if ret != None:   if ret.status == 0:    ret.status = 1    print('书籍《%s》归还成功' % name)    print(ret)   else:    print('书籍《%s》未借出' % name)  else:   print('书籍《%s》不存在' % name)manager = BookManage()manager.Menu()