src/Service/Account/Pricing/Country.php
public function invoke($country = null)
    {
        if (!$country) {
            throw new Exception('$country parameter cannot be blank');
        }

        return new Entity\Pricing($this->exec([
            'country' => $country,
        ]));
    }
public function invoke($country = null)
    {
        if (!$country) {
            throw new Exception('$country parameter cannot be blank');
        }

        return new Entity\Pricing($this->exec([
            'country' => $country,
        ]));
    }
@param string $country

@return Entity\Pricing
@throws Exception