Their mix of explicit lyrics, accordions, tubas and 12-string acoustic guitars make for an odd cross between gangsta rap and polka-esque folk music.

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Along the way, he's also stirred up controversy on several occasions, catching criticism for exploiting his criminal past, as well as for his sexually explicit lyrics and concert shenanigans.

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This year the Rolling Stones were censored during their Super Bowl half-time slot after some lyrics were deemed sexually explicit.

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The music industry already places parental advisory "explicit content" labels on records with sexually graphic or violent lyrics, but does not give details of the offensive material.

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