def add_transition(self, name, transition):
        """
        Add a transition to the start of the transition list.

        Parameter `transition`: a ready-made transition 3-tuple.

        Exception: `DuplicateTransitionError`.
        """
        if name in self.transitions:
            raise DuplicateTransitionError(name)
        self.transition_order[:0] = [name]
        self.transitions[name] = transition
dataset/ETHPy150Open adieu/allbuttonspressed/docutils/statemachine.py/State.add_transition/original