You can scrape the paint from the socket faces, but don't poke anything into the holes, naturally. Also don't use anything wet when you do this, and it could be a good idea to turn the electrics off. I can't see there being any paint inside the sockets themselves as obviously they were left in place when the place was painted. He should have covered the sockets with masking tape anyway, so why not ask him to come back and sort it?
John, April 2009