code: public static <I, O> CompactMealy<I, O> pruneTransitionsWithOutput(MealyMachine<?, I, ?, O> in,
                                                                         Alphabet<I> inputs,
                                                                         Collection<? super O> outputs) {
          return filterByOutput(in, inputs, o -> !outputs.contains(o));
      }
docs: Returns a Mealy machine with all transitions removed that have one of the specified output values. The resulting
  Mealy machine will not contain any unreachable states.
  
  @param in
  the input Mealy machine
  @param inputs
  the input alphabet
  @param outputs
  the outputs to remove
  
  @return a Mealy machine with all transitions removed that have one of the specified outputs.