Issue #18743: Fix references to non-existant "StringIO" module
in docstrings and comments.
diff --git a/Lib/gzip.py b/Lib/gzip.py
index 67fe1d4..2fd03fa 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -144,7 +144,7 @@
non-trivial value.
The new class instance is based on fileobj, which can be a regular
- file, a StringIO object, or any other object which simulates a file.
+ file, an io.BytesIO object, or any other object which simulates a file.
It defaults to None, in which case filename is opened to provide
a file object.