diff -r 4950ae4d034f -r 566daffc607d hgext/show.py
--- a/hgext/show.py	Wed Jul 19 13:17:49 2017 -0700
+++ b/hgext/show.py	Wed Apr 03 11:21:27 2019 -0700
@@ -243,7 +243,7 @@
     else:
         newheads = set()
 
-    allrevs = set(stackrevs) | newheads | set([baserev])
+    allrevs = set(stackrevs) | newheads | {baserev}
     nodelen = longestshortest(repo, allrevs)
 
     try: