private static Set<String> getDuplicateKeywordArguments(@NotNull PyArgumentList node) {
    final Set<String> keywordArgumentNames = new HashSet<>();
    final Set<String> results = new HashSet<>();
    for (PyExpression argument : node.getArguments()) {
      if (argument instanceof PyKeywordArgument) {
        final String keyword = ((PyKeywordArgument)argument).getKeyword();
        if (keywordArgumentNames.contains(keyword)) {
          results.add(keyword);
        }
        keywordArgumentNames.add(keyword);
      }
    }
    return results;
  }
private static Set<String> getDuplicateKeywordArguments(@NotNull PyArgumentList node)