def METHOD_NAME(self, start, end, ratio, supervisees):
    """
    Notify supervisors about their supervisees.
    :param supervisees: dict whereas key is id of supervisee and
                        value as a worktime dict of
                        reported, expected, delta, ratio and balance
    """
    supervisors = get_user_model().objects.all_supervisors()
    subject = "[Timed] Report supervisees with shorttime"
    from_email = settings.DEFAULT_FROM_EMAIL
    mails = []
    for supervisor in supervisors:
        suspects = supervisor.supervisees.filter(
            id__in=supervisees.keys()
        ).order_by("first_name")
        suspects_shorttime = [
            (suspect, supervisees[suspect.id]) for suspect in suspects
        ]
        if suspects.count() > 0 and supervisor.email:
            body = template.render(
                {
                    "start": start,
                    "end": end,
                    "ratio": ratio,
                    "suspects": suspects_shorttime,
                }
            )
            mails.append(
                EmailMessage(
                    subject=subject,
                    body=body,
                    from_email=from_email,
                    to=[supervisor.email],
                    headers=settings.EMAIL_EXTRA_HEADERS,
                )
            )
    if len(mails) > 0:
        connection = get_connection()
        connection.send_messages(mails)
        Notification.objects.create(
            notification_type=Notification.SUPERVISORS_SHORTTIME, sent_at=now()
        )