public function activity($notifyEmail = NULL, $dateFrom = NULL, $dateTo = NULL, array $tags = array(), array $senders = array(), array $states = array(), array $apiKeys = array()){
        return $this->request('activity', array(
            'notify_email' => $notifyEmail,
            'date_from' => $dateFrom,
            'date_to' => $dateTo,
            'tags' => $tags,
            'senders' => $senders,
            'states' => $states,
            'api_keys' => $apiKeys
        ));
    }