'Onaccept routine for response statuses:
- only one status can be the default
@param form: the FORM'

@staticmethod
def response_status_onaccept(form):

    form_vars = form.vars
    try:
        record_id = form_vars.id
    except AttributeError:
        record_id = None
    if (not record_id):
        return
    table = current.s3db.dvr_response_status
    db = current.db
    if form_vars.get('is_default'):
        db((table.id != record_id)).update(is_default=False)
    if form_vars.get('is_default_closure'):
        db((table.id == record_id)).update(is_closed=True)
        db((table.id != record_id)).update(is_default_closure=False)
