from guardian import GuardState

class INIT(GuardState):
    def run(self):
        return 'A'

class A(GuardState):
    def run(self):
        return True

class B(GuardState):
    pass

class C(GuardState):
    def run(self):
        return True

edges = [
    ('A', 'B'),
    ('B', 'C'),
    ]