php

public function addTierPrice(array $tierPriceData)
    {
        $rowNumber = $this->getControlCount('fieldset', 'tier_price_row');
        $this->addParameter('tierPriceId', $rowNumber);
        $this->clickButton('add_tier_price', false);
        $this->fillForm($tierPriceData, 'prices');
    }