handles nested loops; doesn't handle tuples
handles nested loops; doesn't handle tuples

so now something like:

	with concur:
	    for x in [1, 2]:
	        for y in [3, 4]:
		    foo(x, y)

will expand to:

	with concur:
	    foo(1, 3)
	    foo(1, 4)
	    foo(2, 3)
	    foo(2, 4)

(although perhaps in a different order--the order is considered
unimportant)

BBN-Q/pyqgl2,BBN-Q/pyqgl2