--- a/mercurial/pycompat.py	Sun Mar 19 14:23:30 2017 -0400
+++ b/mercurial/pycompat.py	Sun Mar 19 14:12:38 2017 -0400
@@ -57,6 +57,7 @@
     if sysexecutable:
         sysexecutable = os.fsencode(sysexecutable)
     stringio = io.BytesIO
+    maplist = lambda *args: list(map(*args))
 
     # TODO: .buffer might not exist if std streams were replaced; we'll need
     # a silly wrapper to make a bytes stream backed by a unicode one.
@@ -251,6 +252,7 @@
     sysexecutable = sys.executable
     shlexsplit = shlex.split
     stringio = cStringIO.StringIO
+    maplist = map
 
 empty = _queue.Empty
 queue = _queue.Queue