如何在Django admin中按值列表进行过滤？

from .models import Book
from django.contrib import admin
from django.contrib.admin import SimpleListFilter

class BookTypeFilter(SimpleListFilter):
    title = 'Book Type'  # 过滤器的标题

    parameter_name = 'book_type'  # 查询参数的名称

    def lookups(self, request, model_admin):
        # 返回一个包含过滤选项的元组列表
        return (
            ('fiction', 'Fiction'),
            ('non-fiction', 'Non-Fiction'),
        )

    def queryset(self, request, queryset):
        # 根据查询参数的值过滤查询集
        if self.value() == 'fiction':
            return queryset.filter(book_type='Fiction')
        elif self.value() == 'non-fiction':
            return queryset.filter(book_type='Non-Fiction')

@admin.register(Book)
class BookAdmin(admin.ModelAdmin):
    list_filter = (BookTypeFilter,)