Lambda Scoping

[Gerson Kurz]

The following code
...
funcs = []
for instance in range(10):
    funcs.append( lambda: instance )
print map(apply,funcs)

funcs = []
for instance in range(10):
    funcs.append( lambda instance=instance: instance )
print map(apply,funcs)
...
prints

[9, 9, 9, 9, 9, 9, 9, 9, 9, 9]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

which I sort-of understand (I figure, in "lambda: instance" instance
is a lazy expression; "lambda instance=instance: instance" the
expression itself - "instance" - is a lazy expression, too, but the
argument list is not.) However, can anybody please explain this more
detailed?