I am dealing with unicode strings returned by the python-lastfm library.
I assume somewhere on the way, the library gets the encoding wrong and returns a unicode str
You have to convert your unicode string into a standard string using some encoding e.g. utf-8:
some_unicode_string.encode('utf-8')
Apart from that: this is a dupe of
BeautifulSoup findall with class attribute- unicode encode error
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