--- a/mercurial/pure/osutil.py	Mon Feb 21 13:03:43 2022 -0700
+++ b/mercurial/pure/osutil.py	Mon Feb 21 13:08:28 2022 -0700
@@ -220,7 +220,7 @@
             err.errno, '%s: %s' % (encoding.strfromlocal(name), err.strerror)
         )
 
-    class posixfile(object):
+    class posixfile:
         """a file object aiming for POSIX-like semantics
 
         CPython's open() returns a file that was opened *without* setting the