Iterating over lists in Python

Note to self: It's a bad idea to change a list in the middle of a loop iterating over it. The following doesn't work:

for item in list:
    if foo:
        list.remove(list)

And must be replaced with:

for item in list[:]:
    if foo:
        list.remove(list)

On the wrong way, the loop doesn't execute on items positioned immediately after the removed ones. This has cost me a big amount of debugging time...