[jogloran]

Ruby also lets you do this in function definitions. Python doesn't special-case the underscore like Ruby does -- while I have occasionally wished otherwise, it is at least consistent with Python's language design principles that the special case doesn't exist.

[paul-woolcock]

I don't have a source for this, but it is my understanding that, even though the python interpreter doesn't special-case the "_" variable name, it is a convention to use the underscore in the same situations in python as are described in ruby in the article.

[jogloran]

Apart from the special meaning of the underscore in interactive mode, and the function _() in Django, I don't think it's common to use _ as a placeholder in Python. I sometimes do it regardless, hoping its meaning should be clear enough, but it's less suitable than in Ruby because you can't use it to ignore multiple arguments.