This is obviously not a guitar song, but as close as I can get to it is this.
Verse, i.e. 1
G. C D G B
I believe, submarines (backing vocals)
G. C D G. B
Underneath, deep blue sea (backing vocals)
G. C. D G B
Saw the flag, Japanese (backing vocals)
G. C D. G. B
No one will, believe me (backing vocals)
Chorus I.e. Chorus 1
Em. D. G
Ran back to the town folk and I told the people how
Em. D. C.
I've seen a submarine and everyone laughed and laughed
And then back to normal. It's pretty much just that the whole time, but I apologise for any lyrics that ate wrong