'Given a book, return the list of author sort strings
for the book\'s authors'

def authors_sort_strings(self, id, index_is_id=False):

    id = (id if index_is_id else self.id(id))
    aut_strings = self.conn.get('\n                                                                                                SELECT    sort\n                                                                                                FROM    authors,    books_authors_link    as    bl\n                                                                                                WHERE    bl.book=?    and    authors.id=bl.author\n                                                                                                ORDER    BY    bl.id', (id,))
    result = []
    for (sort,) in aut_strings:
        result.append(sort)
    return result
