private boolean parseKeyValueExpression() {
    final SyntaxTreeBuilder.Marker marker = myBuilder.mark();
    if (!parseSingleExpression(false)) {
      marker.drop();
      return false;
    }
    checkMatches(PyTokenTypes.COLON, message("PARSE.expected.colon"));
    if (!parseSingleExpression(false)) {
      myBuilder.error(message("value.expression.expected"));
      marker.drop();
      return false;
    }
    marker.done(PyElementTypes.KEY_VALUE_EXPRESSION);
    return true;
  }
private boolean parseKeyValueExpression()