def METHOD_NAME(self, person_link):
    roles = set()
    if getattr(person_link, 'is_submitter', False):
        # ContributionPersonLink has a property that checks the ACL
        roles.add('submitter')
    if person_link.is_speaker:
        roles.add('speaker')
    if person_link.author_type == AuthorType.primary:
        roles.add('author')
    if person_link.author_type == AuthorType.secondary:
        roles.add('coauthor')
    return roles