As played by The Whistlebinkies & Ted McKenna on their s/t album (1976), followed by "Morrison’s" and "Do You Want Any More". I never heard it anywhere else, maybe it’s composed by them…?
This is a simple yet catchy tune, with a strong emphasis on rhythm (okay, this was kind of redundant, eh?). I especially like the alternative endings of the C and D part, as simple as they are. To play it on the whistle, you need an additional low C hole; replacing the low Cs with Es also works well though. What am I babbling, you know how to fold. :-)
Ah, I just found it uploaded on YT: