private boolean parseClassPatternArgument() {
    if (atToken(PyTokenTypes.IDENTIFIER) && myBuilder.lookAhead(1) == PyTokenTypes.EQ) {
      SyntaxTreeBuilder.Marker mark = myBuilder.mark();
      nextToken();
      nextToken();
      if (!parsePattern()) {
        myBuilder.error(PyParsingBundle.message("PARSE.expected.pattern"));
      }
      mark.done(PyElementTypes.KEYWORD_PATTERN);
      return true;
    }
    return parsePattern();
  }
private boolean parseClassPatternArgument()