How to use the granary.microformats2.render_content function in granary

def _prepare_activity(a, reader=True):
  """Preprocesses an activity to prepare it to be rendered as Atom.

  Modifies a in place.

  Args:
    a: ActivityStreams 1 activity dict
    reader: boolean, whether the output will be rendered in a feed reader.
      Currently just includes location if True, not otherwise.
  """
  act_type = source.object_type(a)
  obj = util.get_first(a, 'object', default={})
  primary = obj if (not act_type or act_type == 'post') else a

  # Render content as HTML; escape &s
  obj['rendered_content'] = _encode_ampersands(microformats2.render_content(
    primary, include_location=reader, render_attachments=True,
    # Readers often obey CSS white-space: pre strictly and don't even line wrap,
    # so don't use it.
    # https://forum.newsblur.com/t/android-cant-read-line-pre-formatted-lines/6116
    white_space_pre=False))

  # Make sure every activity has the title field, since Atom  requires
  # the title element.
  if not a.get('title'):
    a['title'] = util.ellipsize(_encode_ampersands(
      a.get('displayName') or a.get('content') or obj.get('title') or
      obj.get('displayName') or obj.get('content') or 'Untitled'))

  # strip HTML tags. the Atom spec says title is plain text:
  # http://atomenabled.org/developers/syndication/#requiredEntryElements
  a['title'] = xml.sax.saxutils.escape(util.parse_html(a['title']).get_text(''))

def render(source, activity, base):
    obj = activity.get('object') or activity
    content = microformats2.render_content(obj)
    embed = source.embed_post(base)

    type = as_source.object_type(activity)
    content = activity.get('content', '')
    if type == 'share' and not content:
      content = 'retweeted this.'

    rendered = embed + content if type == 'comment' else content + embed

    mf2_class = {'like': 'u-like-of',
                 'share': 'u-repost-of',
                 }.get(type, 'in-reply-to')
    url = (obj.get('inReplyTo') or [{}])[0].get('url') or base.get('url')
    rendered += """
<a href="%s" class="%s"></a>
<a href="%s" class="u-syndication"></a>

item = fg.add_entry()
    url = obj.get('url')
    id = obj.get('id') or url
    item.id(id)
    item.link(href=url)
    item.guid(url, permalink=True)

    # title (required)
    title = (obj.get('title') or obj.get('displayName') or
             util.ellipsize(obj.get('content', '-')))
    # strip HTML tags
    title = util.parse_html(title).get_text('').strip()
    item.title(title)

    content = microformats2.render_content(
      obj, include_location=True, render_attachments=True, render_image=True)
    if not content:
      content = obj.get('summary')
    if content:
      item.content(content, type='CDATA')

    categories = [
      {'term': t['displayName']} for t in obj.get('tags', [])
      if t.get('displayName') and
      t.get('verb') not in ('like', 'react', 'share') and
      t.get('objectType') not in ('article', 'person', 'mention')]
    item.category(categories)

    author = obj.get('author', {})
    author = {
      'name': author.get('displayName') or author.get('username'),

_prepare_actor(elem.get('actor'))

  # normalize attachments, render attached notes/articles
  attachments = a.get('attachments') or obj.get('attachments') or []
  for att in attachments:
    att['stream'] = util.get_first(att, 'stream')
    type = att.get('objectType')

    if type == 'image':
      att['image'] = util.get_first(att, 'image')
      image_atts.append(att['image'])
      continue

    image_urls_seen |= set(util.get_urls(att, 'image'))
    if type in ('note', 'article'):
      html = microformats2.render_content(
        att, include_location=reader, render_attachments=True,
        white_space_pre=False)
      author = att.get('author')
      if author:
        name = microformats2.maybe_linked_name(
          microformats2.object_to_json(author).get('properties') or {})
        html = '%s: %s' % (name.strip(), html)
      children.append(html)

  # render image(s) that we haven't already seen
  for image in image_atts + util.get_list(obj, 'image'):
    if not image:
      continue
    url = image.get('url')
    parsed = urllib.parse.urlparse(url)
    rest = urllib.parse.urlunparse(('', '') + parsed[2:])

def image_url(obj):
    return util.get_first(obj, 'image', {}).get('url')

  def actor_name(obj):
    return obj.get('displayName') or obj.get('username')

  if not actor:
    actor = {}

  items = []
  for activity in activities:
    obj = activity.get('object') or activity
    if obj.get('objectType') == 'person':
      continue
    author = obj.get('author', {})
    content = microformats2.render_content(
            obj, include_location=True, render_attachments=True)
    obj_title = obj.get('title') or obj.get('displayName')
    item = {
      'id': obj.get('id') or obj.get('url'),
      'url': obj.get('url'),
      'image': image_url(obj),
      'title': obj_title if mf2util.is_name_a_title(obj_title, content) else None,
      'summary': obj.get('summary'),
      'content_html': content,
      'date_published': obj.get('published'),
      'date_modified': obj.get('updated'),
      'author': {
        'name': actor_name(author),
        'url': author.get('url'),
        'avatar': image_url(author),
      },