如何在Django2.1中设置for循环内模板中的变量？

{% with variable_name=expression %}
    <!-- 使用variable_name -->
{% endwith %}

from django.shortcuts import render

def blog_list(request):
    posts = [
        {'title': 'First Post', 'content': 'This is the first post content...'},
        {'title': 'Second Post', 'content': 'This is the second post content...'},
        # 更多帖子...
    ]
    return render(request, 'blog_list.html', {'posts': posts})

{% for post in posts %}
    <div class="post">
        <h2>{{ post.title }}</h2>
        {% with summary=post.content|truncatechars:100 %}
            <p>{{ summary }}</p>
        {% endwith %}
    </div>
{% endfor %}