Pink has refused to write a song for troubled chart rival Britney Spears because she's an "entertainer" instead of a "real singer". The outspoken pop star would prefer to pen material for artists like Amy Winehouse, whose brash attitude can do justice to her tracks. She says, "Not because I don't like (Spears) - I do think she's crazy enough to do one of my songs. But it's very hard for me to let go of my songs and the only people I write for are real singers - not that she's not a real singer, but she's more of an entertainer. "When I mean real singers, I mean the likes of Lauryn Hill, Faith Hill - and I'd write for Amy Winehouse, because you need serious attitude to carry off the dumb stuff I write about."