I just reach in and grab them behind the head, then unhook their tail from around the eggs (They generally uncoil quite a big when you grab them).
A feisty girl gets a hand towel over her head first. Some ball pythons are 'really good moms' and will be ready to kill you as soon as you open the bin, lol. Don't fret over it too much--as soon as you have them off the eggs, they forget why they were upset.