"fileinput.input" unicodedecodeerror: 'charmap' codec can't decode byte 0x90 in position 7818: character maps to <undefined> code example

Example 1: UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 92: character maps to

file = open(filename, encoding="cp437")

Example 2: UnicodeDecodeError: 'charmap' codec can't decode byte 0x9e in position 3359: character maps to

#add the encoding parameter for open method
with open(filename, encoding='utf8') as infile: