code: def _add_devices_from_config(args):
      
      config = _parse_config(args.config)
      for device in config['devices']:
          if args.default:
              if device == "default":
                  raise ValueError('devicename "default" in config is not allowed if default param is set')
              if config['devices'][device]['host'] == args.default:
                  raise ValueError('host set in default param must not be defined in config')
          add(device, config['devices'][device]['host'], config['devices'][device].get('adbkey', ''),
              config['devices'][device].get('adb_server_ip', ''), config['devices'][device].get('adb_server_port', 5037))
docs: Add devices from config.