class Foo:
    def __init__(s):
        s.tapped = False

    def tap(s):
        s.tapped = True

    def untap(s):
        s.tapped = False

bar = Foo();
print bar.tapped #prints False (set in constructor)
bar.tap()
print bar.tapped #prints True
bar.untap()
print bar.tapped #prints False