修改模块的调用方式,不过好像两者都可以用

 	{% for book in books %}
 	 	{{ modules.Book(book) }}
 	 	{% module Book(book) %}
 	{% end %}
(with bugs)书店例子升级版,增加修改功能
(with bugs)书店例子升级版增加修改和单本书籍页面