old_contents: 
  from offenerhaushalt.core import freezer, pages, sites
  
  @freezer.register_generator
  def page():
  	for page in pages:
  		yield {'path': page.path}
  
  @freezer.register_generator
  def site():
  	for site in sites:
  		yield {'slug': site.slug}
new_contents: from offenerhaushalt.core import freezer, pages, sites
  
  
  @freezer.register_generator
  def page():
      for page in pages:
          yield {'path': page.path}
  
  
  @freezer.register_generator
  def site():
      for site in sites:
          yield {'slug': site.slug}
  
  
  @freezer.register_generator
  def embed_site():
      for site in sites:
          yield {'slug': site.slug}
  
subject: Add embed site freeze generator