SampleElements<V> sampleValues =
          ((TestMultimapGenerator<K, V, M>) multimapGenerator.getInnerGenerator()).sampleValues();
      return new SampleElements<>(
          mapEntry(sampleKeys.e0(), createCollection(sampleValues.e0())),
          mapEntry(sampleKeys.e1(), createCollection(sampleValues.e1())),
          mapEntry(sampleKeys.e2(), createCollection(sampleValues.e2())),

   *     may or may not have {@code sampleKey} as a key.
   * @param sampleValue a key of the same type as that contained by {@code multimap}. {@code
   *     multimap} may or may not have {@code sampleValue} as a key.
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>
      void assertMultimapIsUnmodifiable(Multimap<K, V> multimap, K sampleKey, V sampleValue) {

        // Note: The implementation has a quirk where strings with escaped quotes don't get unquoted
        String[] simpleValues = { "simple", "", "no quotes or commas" };

        for (String original : simpleValues) {
            String escaped = KuromojiCSVUtil.quoteEscape(original);
            String[] parsed = KuromojiCSVUtil.parse(escaped);