Fix a typo in the section about type hinting context managers (#4185)

east825 · web-flow · commit 231998a0a13f · 2020-06-05T08:43:43.000-07:00
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -278,7 +278,7 @@ they are not part of the stubbed API.
 
 When adding type annotations for context manager classes, annotate
 the return type of `__exit__` as bool only if the context manager
-sometimes suppresses annotations -- if it sometimes returns `True`
+sometimes suppresses exceptions -- if it sometimes returns `True`
 at runtime. If the context manager never suppresses exceptions,
 have the return type be either `None` or `Optional[bool]`. If you
 are not sure whether exceptions are suppressed or not or if the
