Wrong detection UTF-8 with ö symbol

[sergei-sss]

Hi! I'm not an expert in encoding. Can someone please advise me on what I'm doing wrong? The example seems quite simple, but the result is incorrect. Perhaps, it's assumed to use a library for larger texts?

b = b'Sch\xc3\xb6ne gesunde Pflanzen'
chardet.detect(b)  # {'encoding': 'ISO-8859-9', 'confidence': 0.6294978352301421, 'language': 'Turkish'}
b.decode(chardet.detect(b)['encoding'])  # Result: 'Schöne gesunde Pflanzen'
b.decode("utf-8")  # Result: 'Schöne gesunde Pflanzen'

5.2.0/3.11.7