多次发送GET

Question

我想按类别过滤发送到服务器的帖子：

/?category=IT

但是当我加载此页面时，我想通过GET方法发送下一个参数，例如：

/?category=IT&nav=next

但是该怎么做？如何再次发送类别而不点击它？

当前我的代码如下：

def post_list(request):

categories = Category.objects.order_by('name')
if request.method == 'GET':
    if 'category' in request.GET.keys():
        posts = Post.objects.order_by('-created').\
            filter(category=Category.objects.filter(name=request.GET['category']).first())
    else:
        posts = Post.objects.order_by('-created')
    if 'nav' in request.GET.keys():
        if request.GET['nav'] == 'older':
            pass
        elif request.GET['nav'] == 'newer':
            pass
    return render(request, 'blog/post_list.html', {'newest': posts[0], 'posts': posts[1:],
                                                   'categories': categories})