diff -r 27f1191b1305 -r 3aab2330b7d3 mercurial/upgrade_utils/engine.py
--- a/mercurial/upgrade_utils/engine.py	Mon Apr 19 11:22:24 2021 +0200
+++ b/mercurial/upgrade_utils/engine.py	Mon Apr 19 11:22:24 2021 +0200
@@ -12,7 +12,6 @@
 from ..i18n import _
 from ..pycompat import getattr
 from .. import (
-    changegroup,
     changelog,
     error,
     filelog,
@@ -45,7 +44,7 @@
             flagutil.REVIDX_HASCOPIESINFO,
             replace=True,
         )
-    return changegroup.get_sidedata_helpers(srcrepo, dstrepo._wanted_sidedata)
+    return sidedatamod.get_sidedata_helpers(srcrepo, dstrepo._wanted_sidedata)
 
 
 def _revlogfrompath(repo, rl_type, path):