Django中自定义查询对象的具体使用

# models.pyclass AuthorManager(models.Manager): # 新建一个类，继承自models.Manager  def name_count(self, keywords): # 添加自定义的查询函数   '''统计姓名中含有某些关键字的数量'''    return self.filter(name__contains=keywords).count()      def lt_age(self, age):    '''查询年龄小于指定年龄的信息'''    return self.filter(age__lt=age)class Author(models.Model):  objects = AuthorManager() # 使用创建的自定义类覆盖objects  name = models.CharField(max_length=30, verbose_name='姓名')  age = models.IntegerField(verbose_name='年龄')  email = models.EmailField(null=True, verbose_name='邮箱')  picture = models.ImageField(null=True, upload_to='static/upload/usring', verbose_name='用户头像')  publisher = models.ManyToManyField(Publisher, null=True, verbose_name='出版社')# views.pydef myself(request): '''自定义查询函数''' # 统计名字中包含王字的  num = Author.objects.name_count(keywords='王')   # 查询年龄小于36的作者信息  authors = Author.objects.lt_age(age=36)  return render(request, 'name_count.html', locals())