We study electron antidots using a Hartree-Fock approach and an electron-hole transformation that maps the electron antidot into a quantum dot with finite number of holes. We investigate hole maximum density droplets of a bell shape antidot potential in the integer quantum Hall regime with the filling factor two. Here we give the reasons for why a bell shape antidot potential can lead to spin flip transitions, which can cause the Kondo effect. We identify maximum density droplet states corresponding to the spin states of the Anderson impurity that describe the Kondo effect of the antidot.