For one thing, I think that he meant for this:
while 1:
grid.update()
try:
explorer.next()
except StopIteration:
break
...to be this:
while 1:
grid.update()
try:
explorer.next()
except StopIteration:
break
By the way, "except StopIteration" can be replaced by just: "except",
because there are no futher conditional "except"s.
Ian
