code: public Either<L, R> peek(Consumer<L> leftConsumer, Consumer<R> rightConsumer) {
          return Peek2.peek2(leftConsumer, rightConsumer, this);
      }
docs: Perform side-effects against a wrapped right or left value, returning back the <code>Either</code> unaltered.
  
  @param leftConsumer  the effecting consumer for left values
  @param rightConsumer the effecting consumer for right values
  @return the Either, unaltered