如何在html django中引用外键

from django.db import models

class ParentModel(models.Model):
    # 主模型的字段

class ChildModel(models.Model):
    parent = models.ForeignKey(ParentModel, on_delete=models.CASCADE)
    # 外键字段指向主模型
    # 其他字段

from django.shortcuts import render
from .models import ParentModel

def my_view(request):
    parent_objects = ParentModel.objects.all()
    return render(request, 'my_template.html', {'parents': parent_objects})

{% for parent in parents %}
    <h2>{{ parent }}</h2>
    <ul>
        {% for child in parent.childmodel_set.all %}
            <li>{{ child }}</li>
        {% endfor %}
    </ul>
{% endfor %}