Unicode Decode Error on unpack,py

[b6018718]

First of all thank you for all the work you do.
I am having problems running the unpack script with Python 3.8.1
I'm getting the error:

[i] Analizing header ...
Traceback (most recent call last):
  File "C:\Users\antho\Desktop\Firmware\mstar-bin-tool-master\unpack.py", line 44, in <module>
    headerScript = header[:offset].decode()
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xbf in position 9: invalid start byte

Cheers