Thats pretty funny when taken literal, like this. On the other hand I often do file_str and file_num to help myself.
After a journey into functional programming where single letter variable is almost the norm, I came back hating this redundancy, but after a while I got to see that variables names will pop up in different places, you might as well stick a bit more information in their name just in case you're missing context deep down the stack or in a commit.