diff -r ff72bd52d56a -r 9d2b2df2c2ba mercurial/dispatch.py
--- a/mercurial/dispatch.py	Fri Mar 06 10:52:44 2020 +0100
+++ b/mercurial/dispatch.py	Fri Mar 06 13:27:41 2020 -0500
@@ -514,7 +514,7 @@
     '''
     # util.interpolate can't deal with "$@" (with quotes) because it's only
     # built to match prefix + patterns.
-    replacemap = dict((b'$%d' % (i + 1), arg) for i, arg in enumerate(args))
+    replacemap = {b'$%d' % (i + 1): arg for i, arg in enumerate(args)}
     replacemap[b'$0'] = name
     replacemap[b'$$'] = b'$'
     replacemap[b'$@'] = b' '.join(args)