author_str = ", ".join(related_tag_name(tag)
for tag in book.related_info()['tags'].get('author', ()))
return {
'book': book,
'author_str': author_str,
author_str = ", ".join(related_tag_name(tag)
for tag in book.related_info()['tags'].get('author', ()))
return {
'book': book,
'author_str': author_str,