The list of authors als text, for admin submission list overview.

def author_list(self):
        ''' The list of authors als text, for admin submission list overview.'''
        author_list = [self.submitter] + \
            [author for author in self.authors.all().exclude(pk=self.submitter.pk)]
        return ",\n".join([author.get_full_name() for author in author_list])