class potential:

    def force(self, r):
        pass

    def potential(self, r):
        pass

1a90714aef6ff75f64f09d9f9b3b8bc3090ef72a
<mask token>

class potential:
    <mask token>
    <mask token>

class potential:
    <mask token>

    def potential(self, r):
        pass

class potential:

    def force(self, r):
        pass

    def potential(self, r):
        pass
