@register.simple_tag
def get_post_content(post, template_name='containers/post_related.html',
                     content_field='content', related_name='related_posts',
                     get_related=True, safe=True, divider="<br />",
                     placeholder=settings.OPPS_RELATED_POSTS_PLACEHOLDER):
    if not hasattr(post, content_field):
        return None
    content = getattr(post, content_field, '')

    # Fix embed allowfullscreen
    # TinyMCE BUG
    content = content.replace('allowfullscreen="allowfullscreen"',
                              'allowfullscreen="true"')

    if not get_related:
        return content

    related_posts = getattr(post, related_name, None)

    if not related_posts.exists():
        return mark_safe(content)

    # GET THE TEMPLATE
    t = template.loader.get_template(template_name)
    related_rendered = t.render(template.Context({
        'post': post, related_name: related_posts}))
    # EMBED RELATED POSTS
    if placeholder in content:
        return mark_safe(content.replace(
            placeholder,
            related_rendered
        ))
    else:
        return mark_safe(content + divider + related_rendered)
takes the post and tries to find the related posts to embed inside
dataset/ETHPy150Open opps/opps/opps/containers/templatetags/container_tags.py/get_post_content