Django 5 模板中使用 {% url %} 标签报错的原因是什么？

Question

urlpatterns = [
    path('', views.homePage),
    path('index/', views.homePage),
    path('about/', views.about),
    path('posts/', include(('posts.urls','posts'))),
]

urlpatterns = [
    path('', views.posts_list, name='posts'),
]

<nav>
    <a href="http://127.0.0.1:8000/about">😁about</a>
    <a href="http://127.0.0.1:8000/">😭index</a>
    <a href="{% url 'posts' %}">😫post_list</a>
</nav>