code: def InsertArg(self, string="", **_):
      
      if self.verbose:
        logging.debug("Storing Argument %s", utils.SmartUnicode(string))
  
      # This expression is complete
      if self.current_expression.AddArg(string):
        self.stack.append(self.current_expression)
        self.current_expression = self.expression_cls()
        return self.PopState()
docs: Insert an arg to the current expression.