human
Complete the below
def alert():

    ''''REST controller for CAP Alerts and Components'
    '''
assistant
#Here is the Python code you requested.
    tablename = 'cap_alert'
    def prep(r):
        from s3 import S3OptionsFilter
        resource = r.resource
        table = r.table
        itable = s3db.cap_info
        rows = db((itable.expires < request.utcnow)).select(itable.id, orderby=itable.id)
        expired_ids = (','.join([str(row.id) for row in rows]) or None)
        rows = db((itable.expires >= request.utcnow)).select(itable.id, orderby=itable.id)
        unexpired_ids = default_filter = (','.join([str(row.id) for row in rows]) or None)
        rows = db((table.external == True)).select(table.id, orderby=table.id)
        external_alerts = (','.join([str(row.id) for row in rows]) or None)
        rows = db((table.external != True)).select(table.id, orderby=table.id)
        internal_alerts = default_alert = (','.join([str(row.id) for row in rows]) or None)
        filter_widgets = s3db.get_config(tablename, 'filter_widgets')
        filter_widgets_insert = filter_widgets.insert
        filter_widgets_insert(0, S3OptionsFilter('info.id', label=T('Expiration'), options=OrderedDict([(expired_ids, T('Expired')), (unexpired_ids, T('Unexpired')), ('*', T('All'))]), cols=3, multiple=False, default=default_filter))
        filter_widgets_insert(1, S3OptionsFilter('id', label=T('Source'), options=OrderedDict([(internal_alerts, T('Internal')), (external_alerts, T('External')), ('*', T('All'))]), cols=3, multiple=False, default=default_alert))
        representation = r.representation
        if (representation in ('html', 'aadata')):
            table.msg_type.represent = None
        elif (representation == 'dl'):
            list_fields = ['msg_type', 'info.headline', 'area.name', 'info.priority', 'status', 'scope', 'info.event_type_id', 'info.certainty', 'info.severity', 'info.urgency', 'info.sender_name', 'sent']
            s3db.configure(tablename, list_fields=list_fields)
        elif (representation == 'json'):
            list_fields = ['id', 'identifier', 'msg_type', 'sender', 'sent', 'scope', 'status', 'template_id', 'restriction',...