super easy 'object as var' django templatetag

my_items_tags.py

import re
from django import template
from myapp import MyItems

register = template.Library()

class MyItemsNode(template.Node):
    def __init__(self, obj, var_name):
        self.obj = template.Variable(obj)
        self.var_name = var_name
        
    def render(self, context):
        
        try:
            obj = self.obj.resolve(context)
            context[self.var_name] = MyItems.objects.filter(object=obj)
            return ''
        except template.VariableDoesNotExist:
            return ''


def do_my_items(parser, token):
    try:
        tag_name, arg = token.contents.split(None, 1)
    except ValueError:
        raise template.TemplateSyntaxError, "%r tag requires arguments" % token.contents.split()[0]
    m = re.search(r'(.*?) as (\w+)', arg)
    if not m:
        raise template.TemplateSyntaxError, "%r tag had invalid arguments" % tag_name
    obj, var_name = m.groups()
    return MyItemsNode(obj, var_name)

register.tag('my_items', do_my_items)

snippet.html

{% my_items object as item_list %}
{% if item_list %}
    <ul>
        {% for item in item_list %}
        <li>{{ item.name }}</li>
        {% endfor %}
    </ul>
{% else %}
    <p>no items found.</p>
{% endif %}