error TypeError: a bytes-like object is required, not 'str'

[drepou]

i get this error running reboot_router.py with py version 3.7.3

Python 3.7.3 (default, Dec 20 2019, 18:57:59)
[GCC 8.3.0] on linux

Traceback (most recent call last):
File "./reboot_router.py", line 133, in
sys.exit(main())
File "./reboot_router.py", line 129, in main
reboot(client, ROUTER, USER, PASSWORD)
File "./reboot_router.py", line 109, in reboot
verification_token = login(client, server, user, password)
File "./reboot_router.py", line 92, in login
clientnonce, servernonce, password, salt, iterations).decode('UTF-8')
File "./reboot_router.py", line 44, in get_client_proof
'sha256', password, bytearray.fromhex(salt), iterations)
TypeError: a bytes-like object is required, not 'str'

can you help me ??? it seem that bytearray.fromhex(salt) cause the issue i get strange value
i get this from resquest : 05b956492ed7fa6d9fac08b2a8ea.... ( i give you only partial value for security raison ) and then convert i get :
bytearray(b'\x05\xb9VI.\xd7\xfam\x9f\xac\x08\xb2\xa8\xea\x91;[i\xff\xfb\x80\xdfuS\ ..... for me this not valid hex ???