--- a/hgext/releasenotes.py	Sun Oct 06 13:17:19 2019 -0400
+++ b/hgext/releasenotes.py	Sun Oct 06 13:28:56 2019 -0400
@@ -18,6 +18,7 @@
 import re
 
 from mercurial.i18n import _
+from mercurial.pycompat import open
 from mercurial import (
     config,
     error,