code: def tags(tag_references):
      
      if not tag_references:
          return blank()
  
      tag_row = []
      for tag_detail in tag_references:
          tag = utils.lookup(tag_detail, 'tag', 'name')
          if tag is not None:
              tag_row.append(tag)
  
      return listing(tag_row, separator=', ')
docs: Returns a formatted list of tags.