io.UnsupportedOperation: File or stream is not seekable. with python 3.6

[theooze]

On almalinux 8.x w/ the python36-3.6.8-38.module_el8.5.0+2569+5c5719bc.x86_64 package i get this error:

/usr/local/bin/negotiator-guest -vvv -d
2022-01-03 15:09:38 server.example.com negotiator_guest[18032] DEBUG Automatically selecting appropriate character device based on /sys/class/virtio-ports ..
2022-01-03 15:09:38 server.example.com negotiator_guest[18032] DEBUG Selected character device: /dev/vport1p3
2022-01-03 15:09:38 server.example.com negotiator_guest.cli[18032] ERROR Caught a fatal exception! Terminating ..
Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/negotiator_guest/cli.py", line 123, in main
agent = GuestAgent(character_device=character_device, retry=False)
File "/usr/local/lib/python3.6/site-packages/negotiator_guest/init.py", line 61, in init
handle=custom_open(character_device, 'r+'),
io.UnsupportedOperation: File or stream is not seekable.

this looks like maybe related to a python bug:
https://bugs.python.org/issue20074

if i use python 2.7 on the same guest, i can start the daemon w/o issue and the negotiator-guest daemon and use the client w/o issue.