original_string: public function checkoutService($price, $currency, $locale, $country = null)
      {
          $this->_checkAmount($price);
  
          $params = array(
              'merchant_id' => $this->config['eid'],
              'total_price' => $price,
              'currency' => strtoupper($currency),
              'locale' => strtolower($locale)
          );
  
          if ($country !== null) {
              $params['country'] = $country;
          }
  
          return $this->createTransport()->send(
              new CheckoutServiceRequest($this->config, $params)
          );
      }
code: public function checkoutService($price, $currency, $locale, $country = null)
      {
          $this->_checkAmount($price);
  
          $params = array(
              'merchant_id' => $this->config['eid'],
              'total_price' => $price,
              'currency' => strtoupper($currency),
              'locale' => strtolower($locale)
          );
  
          if ($country !== null) {
              $params['country'] = $country;
          }
  
          return $this->createTransport()->send(
              new CheckoutServiceRequest($this->config, $params)
          );
      }
code_tokens: public function checkoutService ( $ price , $ currency , $ locale , $ country = null ) { $ this -> _checkAmount ( $ price ) ; $ params = array ( 'merchant_id' => $ this -> config [ 'eid' ] , 'total_price' => $ price , 'currency' => strtoupper ( $ currency ) , 'locale' => strtolower ( $ locale ) ) ; if ( $ country !== null ) { $ params [ 'country' ] = $ country ; } return $ this -> createTransport ( ) -> send ( new CheckoutServiceRequest ( $ this -> config , $ params ) ) ; }
docstring: Perform a checkout service request.
  
  @param int|float $price    The total price for the checkout including VAT.
  @param string    $currency ISO 4217 Currency Code
  @param string    $locale   Specify what locale is used by the checkout.
  ISO 639 language and ISO 3166-1 country separated
  by underscore. Example: sv_SE
  @param string    $country  (Optional) Specify what ISO 3166-1 country to use
  for fetching payment methods. If not specified
  the locale country will be used.
  
  @throws RuntimeException  If the curl extension is not loaded
  
  @return CheckoutServiceResponse Response with payment methods
docstring_tokens: Perform a checkout service request .