code: def list_devices():
      device_ids = []
      print("!!!", ArmLinuxDevice.devices)
      for dev_name, dev_info in ArmLinuxDevice.devices.items():
          address = dev_info["address"]
          username = dev_info["username"]
          device_ids.append("%s@%s" % (username, address))
      return device_ids
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import copy
  import os
  import re
  import subprocess
  import random
  import tempfile
  from utils import util
label_desc: Use image node_id 2 for calling the ArmLinuxDevice obj's underlying member method code with example usage: obj.list_devices() and returns: device_ids