Luggage storage st Shanghai Museum

My friend and I are going to be in SH for one day after arriving by train in the morning, before we fly out of PVG that night.

We are looking for a place to store our luggage for the day while we go site-seeing. I heard that luggage can be stored at the museum, but I haven't been able to find much information online. Would it be possible to store 2 large suitcases at the museum, and what would be the procedure for doing so? Thanks for any advice you have! :)