The actual name of the repo is "pretty.c", but the name used for the language/dialect/result/horrorshow[*] is "Pretty C".
The actual code file you include is called "pretty.h", which makes sense since it's a header, of course. Confusing!
Edit: escapes.
[*] Yes, I'm a C programmer, currently hunting for black-marked insulin to combat the rapid-onset diabetic attack from all that sugar. Sorta.