diff -r dc403312a012 -r 88472e743c64 hgext3rd/topic/topicmap.py
--- a/hgext3rd/topic/topicmap.py	Tue Aug 06 11:10:36 2019 +0200
+++ b/hgext3rd/topic/topicmap.py	Tue Aug 06 11:17:38 2019 +0200
@@ -111,7 +111,7 @@
         return ret
     parents = ctx.parents()
 
-    if (not opts.get('amend') and bheads and node not in bheads and not
+    if (not opts.get(b'amend') and bheads and node not in bheads and not
         [x for x in parents if x.node() in bheads and x.branch() == branch]):
         repo.ui.status(_("(consider using topic for lightweight branches."
                          " See 'hg help topic')\n"))