Fix Flake8

Author: AA-Turner

sphinx/highlighting.py

@@ -32,7 +32,7 @@
     from pygments.style import Style
 
 if tuple(map(int, pygments.__version__.split('.')))[:2] < (2, 18):
-    from pygments.formatter import Formatter
+    from pygments.formatter import Formatter  # NoQA: F811
 
     Formatter.__class_getitem__ = lambda cls, name: cls  # type: ignore[attr-defined]