如何使用django-filter构建过滤器类，允许按一个模型字段的多个值进行查询

pip install django-filter

from django.db import models

class Product(models.Model):
    name = models.CharField(max_length=100)
    category = models.CharField(max_length=100)

import django_filters
from .models import Product

class ProductFilter(django_filters.FilterSet):
    categories = django_filters.CharFilter(field_name='category', method='filter_by_categories')

    class Meta:
        model = Product
        fields = ['categories']

    def filter_by_categories(self, queryset, name, value):
        categories = value.split(',')
        return queryset.filter(category__in=categories)

from django.shortcuts import render
from django_filters.views import FilterView
from .models import Product
from .filters import ProductFilter

class ProductListView(FilterView):
    model = Product
    filterset_class = ProductFilter
    template_name = 'product_list.html'

from django.urls import path
from .views import ProductListView

urlpatterns = [
    path('products/', ProductListView.as_view(), name='product_list'),
]

<!-- templates/product_list.html -->
<form method="get">
    <label for="categories">Categories (comma separated):</label>
    <input type="text" name="categories" id="categories" value="{{ request.GET.categories }}">
    <button type="submit">Filter</button>
</form>

<ul>
    {% for product in object_list %}
        <li>{{ product.name }} - {{ product.category }}</li>
    {% endfor %}
</ul>