function get_attributes($attributes)
    {

        // initialize the array that will be returned
        $result = array();

        // if the request was for a single attribute,
        // treat it as an array of attributes
        if (!is_array($attributes)) $attributes = array($attributes);

        // iterate through the array of attributes to look for
        foreach ($attributes as $attribute)

            // if attribute exists
            if (array_key_exists($attribute, $this->attributes))

                // populate the $result array
                $result[$attribute] = $this->attributes[$attribute];

        // return the results
        return $result;

    }