starting reflector

hi there having trouble

root@raspberrypi:/opt/pYSFReflector# python3 ./YSFReflector /opt/pYSFReflector/YSFReflector.ini
  File "./YSFReflector", line 857
    s1 = " ".join([f"{i:02x}" for i in b]) # hex string
can you please iam very new to all this 

thank you