def METHOD_NAME(self, device_type):
    """Get a dict, USBID -> device, for a device class
    @param device_type The type of devices to search. For exmaple, "serial"
      looks for all serial devices connected to this computer
    @return A dict: Device USBID -> device file in /dev
    """
    dir = os.path.join("/dev", device_type, "by-id")
    if os.path.isdir(dir):
        to_ret = dict(
            self._hex_ids([os.path.join(dir, f) for f in os.listdir(dir)])
        )
        return to_ret
    else:
        LOG.error(
            "Could not get %s devices by id. "
            "This could be because your Linux distribution "
            "does not use udev, or does not create /dev/%s/by-id "
            "symlinks. Please submit an issue to github.com/"
            "armmbed/mbed-ls.",
            device_type,
            device_type,
        )
        return {}