def METHOD_NAME(share_owner: ShareOwner):
    if share_owner.user is None:
        return
    tapir_user = share_owner.user
    account_entry_from_welcome_session = ShiftAccountEntry.objects.filter(
        user=tapir_user, is_from_welcome_session=True
    )
    if not share_owner.attended_welcome_session:
        account_entry_from_welcome_session.delete()
        return
    if account_entry_from_welcome_session.exists():
        return
    ShiftAccountEntry.objects.create(
        is_from_welcome_session=True,
        user=tapir_user,
        description="Welcome session / Willkommenstreffen",
        date=datetime.today(),
        value=1,
    )