/**
  * Returns an array of Brand/Model combinations
  */
 public static function astArrayForBrandModelList()
 {
     $astResponseTypes = astPhoneModelModel::all();
     if (count($astResponseTypes) != 0) {
         foreach ($astResponseTypes as $astResponseType) {
             $astArrayForList[$astResponseType->PHONE_MODEL_ID] = $astResponseType->BRAND . ' ' . $astResponseType->MODEL_NAME;
         }
         return $astArrayForList;
     } else {
         $emptyArray = [];
         return $emptyArray;
     }
 }