Mika Happy Ending Waltz???

My guitar teacher played me the song Happy Ending by Mika and the version he played had a waltz by Mika on the end. He has written the music into guitar from piano/vocals and given me it. The music is haunting, and I am completely sure it was actually Mika. I have been desperately trying to find the song so if anyone could give me its name or somewhere I could find it that would be great.