@register.simple_tag(takes_context=True)

def special(context, user):

    organiser = user.groups.filter(name='Conference organisers').exists()

    speaker = user.speaker_profile.presentations.count() != 0

    volunteer = "Volunteer" in ticket_type(context)

    if organiser:

        return "Organizer"

    elif speaker:

        return "Speaker"

    elif volunteer:

        return "Staff"

    else:

        return ""