Comment 18 for bug 1328169

I don't have real links to real code, used by a lot of people, but both Pylint[1] and Eclipse[2] already treat underscore and underscore-prefixed identifiers on local variables as implying that the variable is knowingly unused.

In this case, we can also say confidently that addressing this problem won't create problems for other people: the risk is limited only to false negatives on the unused variable check, and then only for codebases that name local variables with an underscore prefix for some reason other than to ignore unused variable warnings, in spite of existing conventions on that.

It's still totally fair for you to ask for a patch instead of implementing it for free, but I think the likelihood of someone submitting a patch would be much higher if you were to confirm that such a patch (with tests) would be accepted.

[1] http://programmers.stackexchange.com/a/139662
[2] http://stackoverflow.com/q/11486148