import plistlib

plistlib._BinaryPlistParser._unpatched_read_object = plistlib._BinaryPlistParser._read_object

def patched_read_object(self, offset):
    self._fp.seek(offset)
    token = self._fp.read(1)[0]
    tokenH, tokenL = token & 0xF0, token & 0x0F

    if token == 0x80:
        return int.from_bytes(self._fp.read(1 << tokenL), 'big')
    else:
        return self._unpatched_read_object(offset)

plistlib._BinaryPlistParser._read_object = patched_read_object