code: def command(self):
          
          if not self._command_calculated:
  
              self._command_calculated = True
              if self.operation == 'command':
                  try:
                      command_idx = self.split_tokens.index('command:')
                      command = self.split_tokens[command_idx + 1]
                      if command == '{':
                          # workaround for <= 2.2 log files,
                          # where command was not listed separately
                          command = self.split_tokens[command_idx + 2][:-1]
                      self._command = command.lower()
                  except ValueError:
                      pass
  
          return self._command
docs: Extract query pattern from operations.