Make __slots__ entries bytestrings
Make __slots__ entries bytestrings

miloh/spreads,nafraf/spreads,DIYBookScanner/spreads,gareth8118/spreads,nafraf/spreads,DIYBookScanner/spreads,adongy/spreads,gareth8118/spreads,miloh/spreads,DIYBookScanner/spreads,adongy/spreads,gareth8118/spreads,adongy/spreads,nafraf/spreads,miloh/spreads