It struck me that it might be prudent to save some of the bulbs from the discarded set, even though I found two replacement bulbs in the ornament box. I pulled the string from the trash. These are miniature white lights under colored caps. I unscrewed a cap to find the light burnt out. Upon inspection, most of them are burnt out. And the one or two I found that look sound, I can't figure out how to get them out of their socket. Usually there's an edge of a bulb you can get your fingernail under, but these bulbs are inset into the socket. If one bulb does blow out, I have no idea how you replace it!
I did save some of the caps in case one breaks going up and down the stairs to the closet.