--- a/hgext3rd/evolve/compat.py	Thu Apr 19 16:21:44 2018 +0200
+++ b/hgext3rd/evolve/compat.py	Thu Apr 19 16:25:17 2018 +0200
@@ -9,7 +9,6 @@
 import inspect
 
 from mercurial import (
-    copies,
     context,
     mdiff,
     obsolete,
@@ -128,15 +127,6 @@
     if util.safehasattr(ui, 'pager'):
         ui.pager(cmd)
 
-def duplicatecopies(repo, wctx, rev, fromrev, skiprev=None):
-    # cannot use anything else until 4.3 support is dropped.
-    assert wctx.rev() is None
-    if copies.duplicatecopies.__code__.co_argcount < 5:
-        # pre 4.4 duplicatecopies compat
-        copies.duplicatecopies(repo, rev, fromrev, skiprev=skiprev)
-    else:
-        copies.duplicatecopies(repo, wctx, rev, fromrev, skiprev=skiprev)
-
 def memfilectx(repo, ctx, fctx, flags, copied, path):
     # XXX Would it be better at the module level?
     varnames = context.memfilectx.__init__.__code__.co_varnames