code: def add_transition(self, output,
                         probability_func=lambda index: np.ones(len(index), dtype=float),
                         triggered=Trigger.NOT_TRIGGERED):
          
          t = Transition(self, output, probability_func=probability_func, triggered=triggered)
          self.transition_set.append(t)
          return t
docs: Builds a transition from this state to the given state.
  
          output : State
              The end state after the transition.