bpo-36878: Only allow text after `# type: ignore` if first character ASCII (GH-13504)



This disallows things like `# type: ignoreƩ`, which seems wrong.

Also switch to using Py_ISALNUM for the alnum check, for consistency
with other code (and maybe correctness re: locale issues?).


https://bugs.python.org/issue36878
3 files changed