Does anyone know this song, its source, or the music?

THE PRISONER'S SONG

Seven years have I served in state prison
And seven more years must I serve
For knocking down a man on the railroad
And taking his gold watch and chain

CHORUS: Sad, sad, I'm lonely
Sitting in my cell all alone
Thinking of the days of my childhood
And the days when I done wrong

I once had a father and a mother
Sitting in a cottage by the sea
I once had a sister and a brother
I wonder if they ever think of me

richard wright