docs: def eval(self, command):
          """
          @summary: Evaluate Tcl command.
  
          @param command: command to evaluate.
          @return: command output.
          """
          # Some operations (like take ownership) may take long time.
          con_command_out = self._con.send_cmd(command, timeout=256)
          if 'ERROR_SEND_CMD_EXIT_DUE_TO_TIMEOUT' in con_command_out:
              raise Exception('{} - command timeout'.format(command))
          command = command.replace('\\', '/')
          con_command_out = con_command_out.replace('\\', '/')
          command = command.replace('(', '\(').replace(')', '\)')
          command = command.replace('{', '\{').replace('}', '\}')
          m = re.search(command + '(.*)' + '%', con_command_out, re.DOTALL)
          command_out = m.group(1).strip()
          if 'couldn\'t read file' in command_out or 'RuntimeError' in command_out:
              raise Exception(command_out)
          return command_out