def _CombineParenthesis(self):
    for i in range(len(self.stack) - 2):
      if (self.stack[i] == "(" and self.stack[i + 2] == ")" or
          isinstance(self.stack[i + 1], Expression)):
        self.stack[i] = None
        self.stack[i + 2] = None

    self.stack = filter(None, self.stack)
dataset/ETHPy150Open google/grr/grr/lib/lexer.py/SearchParser._CombineParenthesis/operator `and` -> `or`