<?php     
    include_once './app/Mage.php'; 
    Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID); 
 
    $updates_file = "./var/export/website_assign.csv"; 
    $websites = array(1, 2); 
     
    $sku_entry = array(); 
    $updates_handle = fopen($updates_file, 'r'); 
    if($updates_handle) { 
        while($sku_entry = fgetcsv($updates_handle, 1000, ",")) { 
            $sku = $sku_entry[0]; 
            echo "<br>Updating website of " . $sku . " - "; 
            try { 
                $get_item = Mage::getModel('catalog/product')->loadByAttribute('sku', $sku); 
                if ($get_item) { 
                    $get_item->setWebsiteIds($websites); 
                    $get_item->save(); 
                    echo "successful"; 
                } else { 
                    echo "item not found"; 
                } 
            } catch (Exception $e) { 
                echo "Cannot retrieve products from Magento: ".$e->getMessage()."<br>"; 
                return; 
            } 
        } 
    } 
    fclose($updates_handle); 
 
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