Decode examples, ANSI=cp932:

>>> codecs.code_page_decode(1252, b'\x80')
('\u20ac', 1)
>>> codecs.code_page_decode(932, b'\x82')
...
UnicodeDecodeError: 'mbcs' codec can't decode bytes in position 0--1: No mapping for the Unicode character exists in the target code page.
>>> codecs.code_page_decode(932, b'\x82', 'replace')
('・', 1)
>>> codecs.code_page_decode(932, b'\x82', 'ignore')
('', 0)

Oh, the encoding name is wrong in the decoding errors.