TypeError from extract_udevadm_info

[hello-binit]

The stretch_factory.hello_device_utils.extract_udevadm_info() method throws a TypeError if it's unable to find the provided port. Minimal reproducible example:

import stretch_factory.hello_device_utils as hdu
hdu.extract_udevadm_info('/dev/gibberish')

The exception is:

TypeError                                 Traceback (most recent call last)
<ipython-input-5-891b81f5b8aa> in <module>
----> 1 hdu.extract_udevadm_info('/dev/gibberish')

~/.local/lib/python3.10/site-packages/stretch_factory/hello_device_utils.py in extract_udevadm_info(usb_port, ID_NAME)
    577     value = None
    578     dname = bytes(usb_port[5:], 'utf-8')
--> 579     out = exec_process([b'udevadm', b'info', b'-n', dname], True)
    580     if ID_NAME is None:
    581         value = out.decode(encoding='UTF-8')

~/.local/lib/python3.10/site-packages/stretch_factory/hello_device_utils.py in exec_process(cmdline, silent, input, **kwargs)
     80     if returncode != 0:
     81         raise RuntimeError('Got return value %d while executing "%s", stderr output was:\n%s' % (
---> 82         returncode, " ".join(cmdline), stderr.rstrip(b"\n")))
     83     return stdout
     84 

TypeError: sequence item 0: expected str instance, bytes found