diff --git a/hgext/absorb.py b/hgext/absorb.py
--- a/hgext/absorb.py
+++ b/hgext/absorb.py
@@ -726,7 +726,7 @@ class fixupstate(object):
 
     def apply(self):
         """apply fixups to individual filefixupstates"""
-        for path, state in self.fixupmap.iteritems():
+        for path, state in pycompat.iteritems(self.fixupmap):
             if self.ui.debugflag:
                 self.ui.write(_(b'applying fixups to %s\n') % path)
             state.apply()
@@ -736,7 +736,7 @@ class fixupstate(object):
         """-> {path: chunkstats}. collect chunkstats from filefixupstates"""
         return dict(
             (path, state.chunkstats)
-            for path, state in self.fixupmap.iteritems()
+            for path, state in pycompat.iteritems(self.fixupmap)
         )
 
     def commit(self):
@@ -755,7 +755,7 @@ class fixupstate(object):
         chunkstats = self.chunkstats
         if ui.verbose:
             # chunkstats for each file
-            for path, stat in chunkstats.iteritems():
+            for path, stat in pycompat.iteritems(chunkstats):
                 if stat[0]:
                     ui.write(
                         _(b'%s: %d of %d chunk(s) applied\n')
@@ -831,7 +831,7 @@ class fixupstate(object):
         repo = self.repo
         needupdate = [
             (name, self.replacemap[hsh])
-            for name, hsh in repo._bookmarks.iteritems()
+            for name, hsh in pycompat.iteritems(repo._bookmarks)
             if hsh in self.replacemap
         ]
         changes = []
@@ -890,7 +890,7 @@ class fixupstate(object):
         # ctx changes more files (not a subset of memworkingcopy)
         if not set(ctx.files()).issubset(set(memworkingcopy)):
             return False
-        for path, content in memworkingcopy.iteritems():
+        for path, content in pycompat.iteritems(memworkingcopy):
             if path not in pctx or path not in ctx:
                 return False
             fctx = ctx[path]
@@ -922,7 +922,7 @@ class fixupstate(object):
     def _cleanupoldcommits(self):
         replacements = {
             k: ([v] if v is not None else [])
-            for k, v in self.replacemap.iteritems()
+            for k, v in pycompat.iteritems(self.replacemap)
         }
         if replacements:
             scmutil.cleanupnodes(
@@ -968,7 +968,7 @@ def overlaydiffcontext(ctx, chunks):
         if not path or not info:
             continue
         patchmap[path].append(info)
-    for path, patches in patchmap.iteritems():
+    for path, patches in pycompat.iteritems(patchmap):
         if path not in ctx or not patches:
             continue
         patches.sort(reverse=True)
diff --git a/hgext/convert/bzr.py b/hgext/convert/bzr.py
--- a/hgext/convert/bzr.py
+++ b/hgext/convert/bzr.py
@@ -12,7 +12,11 @@ from __future__ import absolute_import
 import os
 
 from mercurial.i18n import _
-from mercurial import demandimport, error
+from mercurial import (
+    demandimport,
+    error,
+    pycompat,
+)
 from . import common
 
 # these do not work with demandimport, blacklist
@@ -195,7 +199,7 @@ class bzr_source(common.converter_source
             if not branch.supports_tags():
                 return {}
             tagdict = branch.tags.get_tag_dict()
-            for name, rev in tagdict.iteritems():
+            for name, rev in pycompat.iteritems(tagdict):
                 bytetags[self.recode(name)] = rev
         return bytetags
 
diff --git a/hgext/convert/common.py b/hgext/convert/common.py
--- a/hgext/convert/common.py
+++ b/hgext/convert/common.py
@@ -411,7 +411,7 @@ class commandline(object):
     def _cmdline(self, cmd, *args, **kwargs):
         kwargs = pycompat.byteskwargs(kwargs)
         cmdline = [self.command, cmd] + list(args)
-        for k, v in kwargs.iteritems():
+        for k, v in pycompat.iteritems(kwargs):
             if len(k) == 1:
                 cmdline.append(b'-' + k)
             else:
diff --git a/hgext/convert/convcmd.py b/hgext/convert/convcmd.py
--- a/hgext/convert/convcmd.py
+++ b/hgext/convert/convcmd.py
@@ -581,7 +581,7 @@ class converter(object):
                         # previous one so we don't end up with extra tag heads
                         tagsparents = [
                             e
-                            for e in self.map.iteritems()
+                            for e in pycompat.iteritems(self.map)
                             if e[1] == tagsparent
                         ]
                         if tagsparents:
diff --git a/hgext/convert/cvs.py b/hgext/convert/cvs.py
--- a/hgext/convert/cvs.py
+++ b/hgext/convert/cvs.py
@@ -19,6 +19,7 @@ from mercurial.pycompat import (
 from mercurial import (
     encoding,
     error,
+    pycompat,
     util,
 )
 from mercurial.utils import (
@@ -319,7 +320,7 @@ class convert_cvs(converter_source):
         if full:
             raise error.Abort(_(b"convert from cvs does not support --full"))
         self._parse()
-        return sorted(self.files[rev].iteritems()), {}, set()
+        return sorted(pycompat.iteritems(self.files[rev])), {}, set()
 
     def getcommit(self, rev):
         self._parse()
diff --git a/hgext/convert/cvsps.py b/hgext/convert/cvsps.py
--- a/hgext/convert/cvsps.py
+++ b/hgext/convert/cvsps.py
@@ -470,7 +470,7 @@ def createlog(ui, directory=None, root=b
 
             # find the branches starting from this revision
             branchpoints = set()
-            for branch, revision in branchmap.iteritems():
+            for branch, revision in pycompat.iteritems(branchmap):
                 revparts = tuple([int(i) for i in revision.split(b'.')])
                 if len(revparts) < 2:  # bad tags
                     continue
diff --git a/hgext/convert/filemap.py b/hgext/convert/filemap.py
--- a/hgext/convert/filemap.py
+++ b/hgext/convert/filemap.py
@@ -126,7 +126,7 @@ class filemapper(object):
         repo belong to the source repo and what parts don't."""
         if self.targetprefixes is None:
             self.targetprefixes = set()
-            for before, after in self.rename.iteritems():
+            for before, after in pycompat.iteritems(self.rename):
                 self.targetprefixes.add(after)
 
         # If "." is a target, then all target files are considered from the
diff --git a/hgext/convert/hg.py b/hgext/convert/hg.py
--- a/hgext/convert/hg.py
+++ b/hgext/convert/hg.py
@@ -34,6 +34,7 @@ from mercurial import (
     merge as mergemod,
     node as nodemod,
     phases,
+    pycompat,
     scmutil,
     util,
 )
@@ -133,7 +134,7 @@ class mercurial_sink(common.converter_si
 
         if missings:
             self.after()
-            for pbranch, heads in sorted(missings.iteritems()):
+            for pbranch, heads in sorted(pycompat.iteritems(missings)):
                 pbranchpath = os.path.join(self.path, pbranch)
                 prepo = hg.peer(self.ui, {}, pbranchpath)
                 self.ui.note(
@@ -227,7 +228,7 @@ class mercurial_sink(common.converter_si
             followcopies=False,
         )
 
-        for file, (action, info, msg) in actions.iteritems():
+        for file, (action, info, msg) in pycompat.iteritems(actions):
             if source.targetfilebelongstosource(file):
                 # If the file belongs to the source repo, ignore the p2
                 # since it will be covered by the existing fileset.
@@ -417,7 +418,7 @@ class mercurial_sink(common.converter_si
         tagparent = tagparent or nodemod.nullid
 
         oldlines = set()
-        for branch, heads in self.repo.branchmap().iteritems():
+        for branch, heads in pycompat.iteritems(self.repo.branchmap()):
             for h in heads:
                 if b'.hgtags' in self.repo[h]:
                     oldlines.update(
@@ -589,7 +590,7 @@ class mercurial_source(common.converter_
         maappend = ma.append
         rappend = r.append
         d = ctx1.manifest().diff(ctx2.manifest())
-        for f, ((node1, flag1), (node2, flag2)) in d.iteritems():
+        for f, ((node1, flag1), (node2, flag2)) in pycompat.iteritems(d):
             if node2 is None:
                 rappend(f)
             else:
@@ -615,7 +616,7 @@ class mercurial_source(common.converter_
         cleanp2 = set()
         if len(parents) == 2:
             d = parents[1].manifest().diff(ctx.manifest(), clean=True)
-            for f, value in d.iteritems():
+            for f, value in pycompat.iteritems(d):
                 if value is None:
                     cleanp2.add(f)
         changes = [(f, rev) for f in files if f not in self.ignored]
diff --git a/hgext/convert/monotone.py b/hgext/convert/monotone.py
--- a/hgext/convert/monotone.py
+++ b/hgext/convert/monotone.py
@@ -103,7 +103,7 @@ class monotone_source(common.converter_s
         # Prepare the command in automate stdio format
         kwargs = pycompat.byteskwargs(kwargs)
         command = []
-        for k, v in kwargs.iteritems():
+        for k, v in pycompat.iteritems(kwargs):
             command.append(b"%d:%s" % (len(k), k))
             if v:
                 command.append(b"%d:%s" % (len(v), v))
diff --git a/hgext/convert/subversion.py b/hgext/convert/subversion.py
--- a/hgext/convert/subversion.py
+++ b/hgext/convert/subversion.py
@@ -151,7 +151,7 @@ def get_log_child(
     def receiver(orig_paths, revnum, author, date, message, pool):
         paths = {}
         if orig_paths is not None:
-            for k, v in orig_paths.iteritems():
+            for k, v in pycompat.iteritems(orig_paths):
                 paths[k] = changedpath(v)
         pickle.dump((paths, revnum, author, date, message), fp, protocol)
 
@@ -245,7 +245,7 @@ class directlogstream(list):
         def receiver(orig_paths, revnum, author, date, message, pool):
             paths = {}
             if orig_paths is not None:
-                for k, v in orig_paths.iteritems():
+                for k, v in pycompat.iteritems(orig_paths):
                     paths[k] = changedpath(v)
             self.append((paths, revnum, author, date, message))
 
@@ -591,7 +591,7 @@ class svn_source(converter_source):
             )
             files = [
                 n
-                for n, e in entries.iteritems()
+                for n, e in pycompat.iteritems(entries)
                 if e.kind == svn.core.svn_node_file
             ]
             self.removed = set()
@@ -681,7 +681,7 @@ class svn_source(converter_source):
                     origpaths = []
                 copies = [
                     (e.copyfrom_path, e.copyfrom_rev, p)
-                    for p, e in origpaths.iteritems()
+                    for p, e in pycompat.iteritems(origpaths)
                     if e.copyfrom_path
                 ]
                 # Apply moves/copies from more specific to general
@@ -712,7 +712,7 @@ class svn_source(converter_source):
                 # be represented in mercurial.
                 addeds = dict(
                     (p, e.copyfrom_path)
-                    for p, e in origpaths.iteritems()
+                    for p, e in pycompat.iteritems(origpaths)
                     if e.action == b'A' and e.copyfrom_path
                 )
                 badroots = set()
@@ -1001,7 +1001,7 @@ class svn_source(converter_source):
             parents = []
             # check whether this revision is the start of a branch or part
             # of a branch renaming
-            orig_paths = sorted(orig_paths.iteritems())
+            orig_paths = sorted(pycompat.iteritems(orig_paths))
             root_paths = [
                 (p, e) for p, e in orig_paths if self.module.startswith(p)
             ]
@@ -1168,7 +1168,7 @@ class svn_source(converter_source):
             path += b'/'
         return (
             (path + p)
-            for p, e in entries.iteritems()
+            for p, e in pycompat.iteritems(entries)
             if e.kind == svn.core.svn_node_file
         )
 
diff --git a/hgext/eol.py b/hgext/eol.py
--- a/hgext/eol.py
+++ b/hgext/eol.py
@@ -367,7 +367,7 @@ def reposetup(ui, repo):
 
     if not repo.local():
         return
-    for name, fn in filters.iteritems():
+    for name, fn in pycompat.iteritems(filters):
         repo.adddatafilter(name, fn)
 
     ui.setconfig(b'patch', b'eol', b'auto', b'eol')
diff --git a/hgext/fastannotate/context.py b/hgext/fastannotate/context.py
--- a/hgext/fastannotate/context.py
+++ b/hgext/fastannotate/context.py
@@ -169,7 +169,7 @@ class annotateopts(object):
 
     def __init__(self, **opts):
         opts = pycompat.byteskwargs(opts)
-        for k, v in self.defaults.iteritems():
+        for k, v in pycompat.iteritems(self.defaults):
             setattr(self, k, opts.get(k, v))
 
     @util.propertycache
@@ -578,7 +578,7 @@ class _annotatecontext(object):
             # find an unresolved line and its linelog rev to annotate
             hsh = None
             try:
-                for (rev, _linenum), idxs in key2idxs.iteritems():
+                for (rev, _linenum), idxs in pycompat.iteritems(key2idxs):
                     if revmap.rev2flag(rev) & revmapmod.sidebranchflag:
                         continue
                     hsh = annotateresult[idxs[0]][0]
@@ -589,7 +589,7 @@ class _annotatecontext(object):
                 # the remaining key2idxs are not in main branch, resolving them
                 # using the hard way...
                 revlines = {}
-                for (rev, linenum), idxs in key2idxs.iteritems():
+                for (rev, linenum), idxs in pycompat.iteritems(key2idxs):
                     if rev not in revlines:
                         hsh = annotateresult[idxs[0]][0]
                         if self.ui.debugflag:
diff --git a/hgext/fastannotate/protocol.py b/hgext/fastannotate/protocol.py
--- a/hgext/fastannotate/protocol.py
+++ b/hgext/fastannotate/protocol.py
@@ -15,6 +15,7 @@ from mercurial import (
     error,
     extensions,
     hg,
+    pycompat,
     util,
     wireprotov1peer,
     wireprotov1server,
@@ -188,7 +189,7 @@ def clientfetch(repo, paths, lastnodemap
         for result in results:
             r = result.result()
             # TODO: pconvert these paths on the server?
-            r = {util.pconvert(p): v for p, v in r.iteritems()}
+            r = {util.pconvert(p): v for p, v in pycompat.iteritems(r)}
             for path in sorted(r):
                 # ignore malicious paths
                 if not path.startswith(b'fastannotate/') or b'/../' in (
diff --git a/hgext/fix.py b/hgext/fix.py
--- a/hgext/fix.py
+++ b/hgext/fix.py
@@ -353,7 +353,9 @@ def cleanup(repo, replacements, wdirwrit
     Useful as a hook point for extending "hg fix" with output summarizing the
     effects of the command, though we choose not to output anything here.
     """
-    replacements = {prec: [succ] for prec, succ in replacements.iteritems()}
+    replacements = {
+        prec: [succ] for prec, succ in pycompat.iteritems(replacements)
+    }
     scmutil.cleanupnodes(repo, replacements, b'fix', fixphase=True)
 
 
@@ -619,7 +621,7 @@ def fixfile(ui, repo, opts, fixers, fixc
     """
     metadata = {}
     newdata = fixctx[path].data()
-    for fixername, fixer in fixers.iteritems():
+    for fixername, fixer in pycompat.iteritems(fixers):
         if fixer.affects(opts, fixctx, path):
             ranges = lineranges(opts, path, basectxs, fixctx, newdata)
             command = fixer.command(ui, path, ranges)
@@ -695,7 +697,7 @@ def writeworkingdir(repo, ctx, filedata,
 
     Directly updates the dirstate for the affected files.
     """
-    for path, data in filedata.iteritems():
+    for path, data in pycompat.iteritems(filedata):
         fctx = ctx[path]
         fctx.write(data, fctx.flags())
         if repo.dirstate[path] == b'n':
diff --git a/hgext/fsmonitor/__init__.py b/hgext/fsmonitor/__init__.py
--- a/hgext/fsmonitor/__init__.py
+++ b/hgext/fsmonitor/__init__.py
@@ -467,12 +467,14 @@ def overridewalk(orig, self, match, subr
             visit.update(f for f in copymap if f not in results and matchfn(f))
     else:
         if matchalways:
-            visit.update(f for f, st in dmap.iteritems() if f not in results)
+            visit.update(
+                f for f, st in pycompat.iteritems(dmap) if f not in results
+            )
             visit.update(f for f in copymap if f not in results)
         else:
             visit.update(
                 f
-                for f, st in dmap.iteritems()
+                for f, st in pycompat.iteritems(dmap)
                 if f not in results and matchfn(f)
             )
             visit.update(f for f in copymap if f not in results and matchfn(f))
diff --git a/hgext/githelp.py b/hgext/githelp.py
--- a/hgext/githelp.py
+++ b/hgext/githelp.py
@@ -116,7 +116,7 @@ def parseoptions(ui, cmdoptions, args):
     opts = dict(
         [
             (k, convert(v)) if isinstance(v, str) else (k, v)
-            for k, v in opts.iteritems()
+            for k, v in pycompat.iteritems(opts)
         ]
     )
 
@@ -132,7 +132,7 @@ class Command(object):
     def __bytes__(self):
         cmd = b"hg " + self.name
         if self.opts:
-            for k, values in sorted(self.opts.iteritems()):
+            for k, values in sorted(pycompat.iteritems(self.opts)):
                 for v in values:
                     if v:
                         if isinstance(v, int):
diff --git a/hgext/hgk.py b/hgext/hgk.py
--- a/hgext/hgk.py
+++ b/hgext/hgk.py
@@ -376,7 +376,9 @@ def view(ui, repo, *etc, **opts):
     b"start interactive history viewer"
     opts = pycompat.byteskwargs(opts)
     os.chdir(repo.root)
-    optstr = b' '.join([b'--%s %s' % (k, v) for k, v in opts.iteritems() if v])
+    optstr = b' '.join(
+        [b'--%s %s' % (k, v) for k, v in pycompat.iteritems(opts) if v]
+    )
     if repo.filtername is None:
         optstr += b'--hidden'
 
diff --git a/hgext/histedit.py b/hgext/histedit.py
--- a/hgext/histedit.py
+++ b/hgext/histedit.py
@@ -2013,7 +2013,7 @@ def _finishhistedit(ui, repo, state, fm)
 
     mapping, tmpnodes, created, ntm = processreplacement(state)
     if mapping:
-        for prec, succs in mapping.iteritems():
+        for prec, succs in pycompat.iteritems(mapping):
             if not succs:
                 ui.debug(b'histedit: %s is dropped\n' % node.short(prec))
             else:
@@ -2051,7 +2051,7 @@ def _finishhistedit(ui, repo, state, fm)
     nodechanges = fd(
         {
             hf(oldn): fl([hf(n) for n in newn], name=b'node')
-            for oldn, newn in mapping.iteritems()
+            for oldn, newn in pycompat.iteritems(mapping)
         },
         key=b"oldnode",
         value=b"newnodes",
@@ -2311,7 +2311,7 @@ def ruleeditor(repo, ui, actions, editco
                     tsum = summary[len(fword) + 1 :].lstrip()
                     # safe but slow: reverse iterate over the actions so we
                     # don't clash on two commits having the same summary
-                    for na, l in reversed(list(newact.iteritems())):
+                    for na, l in reversed(list(pycompat.iteritems(newact))):
                         actx = repo[na.node]
                         asum = _getsummary(actx)
                         if asum == tsum:
@@ -2324,7 +2324,7 @@ def ruleeditor(repo, ui, actions, editco
 
         # copy over and flatten the new list
         actions = []
-        for na, l in newact.iteritems():
+        for na, l in pycompat.iteritems(newact):
             actions.append(na)
             actions += l
 
diff --git a/hgext/infinitepush/__init__.py b/hgext/infinitepush/__init__.py
--- a/hgext/infinitepush/__init__.py
+++ b/hgext/infinitepush/__init__.py
@@ -378,7 +378,7 @@ def _checkheads(orig, pushop):
 
 def wireprotolistkeyspatterns(repo, proto, namespace, patterns):
     patterns = wireprototypes.decodelist(patterns)
-    d = repo.listkeys(encoding.tolocal(namespace), patterns).iteritems()
+    d = pycompat.iteritems(repo.listkeys(encoding.tolocal(namespace), patterns))
     return pushkey.encodekeys(d)
 
 
@@ -392,7 +392,7 @@ def localrepolistkeys(orig, self, namesp
             if pattern.endswith(b'*'):
                 pattern = b're:^' + pattern[:-1] + b'.*'
             kind, pat, matcher = stringutil.stringmatcher(pattern)
-            for bookmark, node in bookmarks.iteritems():
+            for bookmark, node in pycompat.iteritems(bookmarks):
                 if matcher(bookmark):
                     results[bookmark] = node
         return results
@@ -514,7 +514,7 @@ def _generateoutputparts(head, bundlerep
                     if part.type == b'changegroup':
                         haschangegroup = True
                     newpart = bundle2.bundlepart(part.type, data=part.read())
-                    for key, value in part.params.iteritems():
+                    for key, value in pycompat.iteritems(part.params):
                         newpart.addparam(key, value)
                     parts.append(newpart)
 
@@ -757,7 +757,7 @@ def _saveremotebookmarks(repo, newbookma
             # saveremotenames expects 20 byte binary nodes for branches
             branches[rname].append(bin(hexnode))
 
-    for bookmark, hexnode in newbookmarks.iteritems():
+    for bookmark, hexnode in pycompat.iteritems(newbookmarks):
         bookmarks[bookmark] = hexnode
     remotenamesext.saveremotenames(repo, remotepath, branches, bookmarks)
 
@@ -767,7 +767,7 @@ def _savelocalbookmarks(repo, bookmarks)
         return
     with repo.wlock(), repo.lock(), repo.transaction(b'bookmark') as tr:
         changes = []
-        for scratchbook, node in bookmarks.iteritems():
+        for scratchbook, node in pycompat.iteritems(bookmarks):
             changectx = repo[node]
             changes.append((scratchbook, changectx.node()))
         repo._bookmarks.applychanges(repo, tr, changes)
@@ -1005,7 +1005,7 @@ def storetobundlestore(orig, repo, op, u
                 bundle2._processpart(op, part)
             else:
                 bundlepart = bundle2.bundlepart(part.type, data=part.read())
-                for key, value in part.params.iteritems():
+                for key, value in pycompat.iteritems(part.params):
                     bundlepart.addparam(key, value)
 
                 # Certain parts require a response
@@ -1092,7 +1092,7 @@ def processparts(orig, repo, op, unbundl
                     # differs from previous behavior, we need to put it behind a
                     # config flag for incremental rollout.
                     bundlepart = bundle2.bundlepart(part.type, data=part.read())
-                    for key, value in part.params.iteritems():
+                    for key, value in pycompat.iteritems(part.params):
                         bundlepart.addparam(key, value)
 
                     # Certain parts require a response
@@ -1273,7 +1273,9 @@ def _maybeaddpushbackpart(op, bookmark, 
                 b'new': newnode,
                 b'old': oldnode,
             }
-            op.reply.newpart(b'pushkey', mandatoryparams=params.iteritems())
+            op.reply.newpart(
+                b'pushkey', mandatoryparams=pycompat.iteritems(params)
+            )
 
 
 def bundle2pushkey(orig, op, part):
diff --git a/hgext/infinitepush/bundleparts.py b/hgext/infinitepush/bundleparts.py
--- a/hgext/infinitepush/bundleparts.py
+++ b/hgext/infinitepush/bundleparts.py
@@ -13,6 +13,7 @@ from mercurial import (
     error,
     extensions,
     node as nodemod,
+    pycompat,
     revsetlang,
     util,
 )
@@ -67,7 +68,7 @@ def getscratchbranchparts(repo, peer, ou
     parts.append(
         bundle2.bundlepart(
             scratchbranchparttype.upper(),
-            advisoryparams=params.iteritems(),
+            advisoryparams=pycompat.iteritems(params),
             data=cg,
         )
     )
diff --git a/hgext/infinitepush/sqlindexapi.py b/hgext/infinitepush/sqlindexapi.py
--- a/hgext/infinitepush/sqlindexapi.py
+++ b/hgext/infinitepush/sqlindexapi.py
@@ -14,6 +14,8 @@ import time
 import warnings
 import mysql.connector
 
+from mercurial import pycompat
+
 from . import indexapi
 
 
@@ -178,7 +180,7 @@ class sqlindexapi(indexapi.indexapi):
             self.sqlconnect()
         args = []
         values = []
-        for bookmark, node in bookmarks.iteritems():
+        for bookmark, node in pycompat.iteritems(bookmarks):
             args.append(b'(%s, %s, %s)')
             values.extend((bookmark, node, self.reponame))
         args = b','.join(args)
diff --git a/hgext/journal.py b/hgext/journal.py
--- a/hgext/journal.py
+++ b/hgext/journal.py
@@ -126,7 +126,7 @@ def recordbookmarks(orig, store, fp):
     repo = store._repo
     if util.safehasattr(repo, b'journal'):
         oldmarks = bookmarks.bmstore(repo)
-        for mark, value in store.iteritems():
+        for mark, value in pycompat.iteritems(store):
             oldvalue = oldmarks.get(mark, node.nullid)
             if value != oldvalue:
                 repo.journal.record(bookmarktype, mark, oldvalue, value)
diff --git a/hgext/keyword.py b/hgext/keyword.py
--- a/hgext/keyword.py
+++ b/hgext/keyword.py
@@ -507,7 +507,7 @@ def demo(ui, repo, *args, **opts):
         kwmaps = _defaultkwmaps(ui)
         if uikwmaps:
             ui.status(_(b'\tdisabling current template maps\n'))
-            for k, v in kwmaps.iteritems():
+            for k, v in pycompat.iteritems(kwmaps):
                 ui.setconfig(b'keywordmaps', k, v, b'keyword')
     else:
         ui.status(_(b'\n\tconfiguration using current keyword template maps\n'))
@@ -521,7 +521,7 @@ def demo(ui, repo, *args, **opts):
     ui.writenoi18n(b'[extensions]\nkeyword =\n')
     demoitems(b'keyword', ui.configitems(b'keyword'))
     demoitems(b'keywordset', ui.configitems(b'keywordset'))
-    demoitems(b'keywordmaps', kwmaps.iteritems())
+    demoitems(b'keywordmaps', pycompat.iteritems(kwmaps))
     keywords = b'$' + b'$\n$'.join(sorted(kwmaps.keys())) + b'$\n'
     repo.wvfs.write(fn, keywords)
     repo[None].add([fn])
diff --git a/hgext/largefiles/overrides.py b/hgext/largefiles/overrides.py
--- a/hgext/largefiles/overrides.py
+++ b/hgext/largefiles/overrides.py
@@ -688,7 +688,7 @@ def copiespathcopies(orig, ctx1, ctx2, m
     copies = orig(ctx1, ctx2, match=match)
     updated = {}
 
-    for k, v in copies.iteritems():
+    for k, v in pycompat.iteritems(copies):
         updated[lfutil.splitstandin(k) or k] = lfutil.splitstandin(v) or v
 
     return updated
diff --git a/hgext/largefiles/remotestore.py b/hgext/largefiles/remotestore.py
--- a/hgext/largefiles/remotestore.py
+++ b/hgext/largefiles/remotestore.py
@@ -11,6 +11,7 @@ from mercurial.i18n import _
 
 from mercurial import (
     error,
+    pycompat,
     util,
 )
 
@@ -49,7 +50,9 @@ class remotestore(basestore.basestore):
     def exists(self, hashes):
         return dict(
             (h, s == 0)
-            for (h, s) in self._stat(hashes).iteritems()  # dict-from-generator
+            for (h, s) in pycompat.iteritems(
+                self._stat(hashes)
+            )  # dict-from-generator
         )
 
     def sendfile(self, filename, hash):
diff --git a/hgext/lfs/__init__.py b/hgext/lfs/__init__.py
--- a/hgext/lfs/__init__.py
+++ b/hgext/lfs/__init__.py
@@ -381,7 +381,7 @@ def lfsfiles(context, mapping):
     def pointer(v):
         # In the file spec, version is first and the other keys are sorted.
         sortkeyfunc = lambda x: (x[0] != b'version', x)
-        items = sorted(pointers[v].iteritems(), key=sortkeyfunc)
+        items = sorted(pycompat.iteritems(pointers[v]), key=sortkeyfunc)
         return util.sortdict(items)
 
     makemap = lambda v: {
diff --git a/hgext/lfs/pointer.py b/hgext/lfs/pointer.py
--- a/hgext/lfs/pointer.py
+++ b/hgext/lfs/pointer.py
@@ -41,7 +41,7 @@ class gitlfspointer(dict):
 
     def serialize(self):
         sortkeyfunc = lambda x: (x[0] != b'version', x)
-        items = sorted(self.validate().iteritems(), key=sortkeyfunc)
+        items = sorted(pycompat.iteritems(self.validate()), key=sortkeyfunc)
         return b''.join(b'%s %s\n' % (k, v) for k, v in items)
 
     def oid(self):
@@ -63,7 +63,7 @@ class gitlfspointer(dict):
     def validate(self):
         """raise InvalidPointer on error. return self if there is no error"""
         requiredcount = 0
-        for k, v in self.iteritems():
+        for k, v in pycompat.iteritems(self):
             if k in self._requiredre:
                 if not self._requiredre[k].match(v):
                     raise InvalidPointer(
diff --git a/hgext/lfs/wrapper.py b/hgext/lfs/wrapper.py
--- a/hgext/lfs/wrapper.py
+++ b/hgext/lfs/wrapper.py
@@ -25,6 +25,7 @@ from mercurial import (
     exchange,
     exthelper,
     localrepo,
+    pycompat,
     revlog,
     scmutil,
     upgrade,
@@ -138,7 +139,7 @@ def writetostore(self, text, sidedata):
 
     # translate hg filelog metadata to lfs metadata with "x-hg-" prefix
     if hgmeta is not None:
-        for k, v in hgmeta.iteritems():
+        for k, v in pycompat.iteritems(hgmeta):
             metadata[b'x-hg-%s' % k] = v
 
     rawtext = metadata.serialize()
diff --git a/hgext/mq.py b/hgext/mq.py
--- a/hgext/mq.py
+++ b/hgext/mq.py
@@ -2001,7 +2001,7 @@ class queue(object):
                         # we can't copy a file created by the patch itself
                         if dst in copies:
                             del copies[dst]
-                    for src, dsts in copies.iteritems():
+                    for src, dsts in pycompat.iteritems(copies):
                         for dst in dsts:
                             repo.dirstate.copy(src, dst)
                 else:
@@ -4263,7 +4263,7 @@ def extsetup(ui):
     entry[1].extend(mqopt)
 
     def dotable(cmdtable):
-        for cmd, entry in cmdtable.iteritems():
+        for cmd, entry in pycompat.iteritems(cmdtable):
             cmd = cmdutil.parsealiases(cmd)[0]
             func = entry[0]
             if func.norepo:
diff --git a/hgext/rebase.py b/hgext/rebase.py
--- a/hgext/rebase.py
+++ b/hgext/rebase.py
@@ -151,7 +151,7 @@ def _ctxdesc(ctx):
     )
     repo = ctx.repo()
     names = []
-    for nsname, ns in repo.names.iteritems():
+    for nsname, ns in pycompat.iteritems(repo.names):
         if nsname == b'branches':
             continue
         names.extend(ns.names(repo, ctx.node()))
@@ -239,7 +239,7 @@ class rebaseruntime(object):
         f.write(b'%d\n' % int(self.keepbranchesf))
         f.write(b'%s\n' % (self.activebookmark or b''))
         destmap = self.destmap
-        for d, v in self.state.iteritems():
+        for d, v in pycompat.iteritems(self.state):
             oldrev = repo[d].hex()
             if v >= 0:
                 newrev = repo[v].hex()
@@ -489,7 +489,7 @@ class rebaseruntime(object):
             # commits.
             self.storestatus(tr)
 
-        cands = [k for k, v in self.state.iteritems() if v == revtodo]
+        cands = [k for k, v in pycompat.iteritems(self.state) if v == revtodo]
         p = repo.ui.makeprogress(
             _(b"rebasing"), unit=_(b'changesets'), total=len(cands)
         )
@@ -1326,7 +1326,7 @@ def _definedestmap(
             # emulate the old behavior, showing "nothing to rebase" (a better
             # behavior may be abort with "cannot find branching point" error)
             bpbase.clear()
-        for bp, bs in bpbase.iteritems():  # calculate roots
+        for bp, bs in pycompat.iteritems(bpbase):  # calculate roots
             roots += list(repo.revs(b'children(%d) & ancestors(%ld)', bp, bs))
 
         rebaseset = repo.revs(b'%ld::', roots)
@@ -1970,7 +1970,7 @@ def needupdate(repo, state):
 
     # We should be standing on the first as-of-yet unrebased commit.
     firstunrebased = min(
-        [old for old, new in state.iteritems() if new == nullrev]
+        [old for old, new in pycompat.iteritems(state) if new == nullrev]
     )
     if firstunrebased in parents:
         return True
@@ -2121,7 +2121,7 @@ def clearrebased(
         fl = fm.formatlist
         fd = fm.formatdict
         changes = {}
-        for oldns, newn in replacements.iteritems():
+        for oldns, newn in pycompat.iteritems(replacements):
             for oldn in oldns:
                 changes[hf(oldn)] = fl([hf(n) for n in newn], name=b'node')
         nodechanges = fd(changes, key=b"oldnode", value=b"newnodes")
diff --git a/hgext/releasenotes.py b/hgext/releasenotes.py
--- a/hgext/releasenotes.py
+++ b/hgext/releasenotes.py
@@ -161,7 +161,7 @@ class releasenotessections(object):
             custom_sections = getcustomadmonitions(repo)
             if custom_sections:
                 sections.update(custom_sections)
-            self._sections = list(sections.iteritems())
+            self._sections = list(pycompat.iteritems(sections))
         else:
             self._sections = list(DEFAULT_SECTIONS)
 
diff --git a/hgext/remotefilelog/__init__.py b/hgext/remotefilelog/__init__.py
--- a/hgext/remotefilelog/__init__.py
+++ b/hgext/remotefilelog/__init__.py
@@ -502,7 +502,7 @@ def checkunknownfiles(orig, repo, wctx, 
     if isenabled(repo):
         files = []
         sparsematch = repo.maybesparsematch(mctx.rev())
-        for f, (m, actionargs, msg) in actions.iteritems():
+        for f, (m, actionargs, msg) in pycompat.iteritems(actions):
             if sparsematch and not sparsematch(f):
                 continue
             if m in (b'c', b'dc', b'cm'):
diff --git a/hgext/remotefilelog/basestore.py b/hgext/remotefilelog/basestore.py
--- a/hgext/remotefilelog/basestore.py
+++ b/hgext/remotefilelog/basestore.py
@@ -148,7 +148,7 @@ class basestore(object):
 
         filenamemap = self._resolvefilenames(existing.keys())
 
-        for filename, sha in filenamemap.iteritems():
+        for filename, sha in pycompat.iteritems(filenamemap):
             yield (filename, existing[sha])
 
     def _resolvefilenames(self, hashes):
diff --git a/hgext/remotefilelog/datapack.py b/hgext/remotefilelog/datapack.py
--- a/hgext/remotefilelog/datapack.py
+++ b/hgext/remotefilelog/datapack.py
@@ -452,7 +452,7 @@ class mutabledatapack(basepack.mutableba
 
     def createindex(self, nodelocations, indexoffset):
         entries = sorted(
-            (n, db, o, s) for n, (db, o, s) in self.entries.iteritems()
+            (n, db, o, s) for n, (db, o, s) in pycompat.iteritems(self.entries)
         )
 
         rawindex = b''
diff --git a/hgext/remotefilelog/historypack.py b/hgext/remotefilelog/historypack.py
--- a/hgext/remotefilelog/historypack.py
+++ b/hgext/remotefilelog/historypack.py
@@ -518,7 +518,7 @@ class mutablehistorypack(basepack.mutabl
 
         files = (
             (hashlib.sha1(filename).digest(), filename, offset, size)
-            for filename, (offset, size) in self.files.iteritems()
+            for filename, (offset, size) in pycompat.iteritems(self.files)
         )
         files = sorted(files)
 
@@ -554,7 +554,7 @@ class mutablehistorypack(basepack.mutabl
             )
             nodeindexoffset += constants.FILENAMESIZE + len(filename)
 
-            for node, location in sorted(nodelocations.iteritems()):
+            for node, location in sorted(pycompat.iteritems(nodelocations)):
                 nodeindexentries.append(
                     struct.pack(nodeindexformat, node, location)
                 )
diff --git a/hgext/remotefilelog/remotefilelog.py b/hgext/remotefilelog/remotefilelog.py
--- a/hgext/remotefilelog/remotefilelog.py
+++ b/hgext/remotefilelog/remotefilelog.py
@@ -21,6 +21,7 @@ from mercurial import (
     ancestor,
     error,
     mdiff,
+    pycompat,
     revlog,
     util,
 )
@@ -428,7 +429,7 @@ class remotefilelog(object):
             return nullid
 
         revmap, parentfunc = self._buildrevgraph(a, b)
-        nodemap = dict(((v, k) for (k, v) in revmap.iteritems()))
+        nodemap = dict(((v, k) for (k, v) in pycompat.iteritems(revmap)))
 
         ancs = ancestor.ancestors(parentfunc, revmap[a], revmap[b])
         if ancs:
@@ -443,7 +444,7 @@ class remotefilelog(object):
             return nullid
 
         revmap, parentfunc = self._buildrevgraph(a, b)
-        nodemap = dict(((v, k) for (k, v) in revmap.iteritems()))
+        nodemap = dict(((v, k) for (k, v) in pycompat.iteritems(revmap)))
 
         ancs = ancestor.commonancestorsheads(parentfunc, revmap[a], revmap[b])
         return map(nodemap.__getitem__, ancs)
@@ -459,7 +460,7 @@ class remotefilelog(object):
         parentsmap = collections.defaultdict(list)
         allparents = set()
         for mapping in (amap, bmap):
-            for node, pdata in mapping.iteritems():
+            for node, pdata in pycompat.iteritems(mapping):
                 parents = parentsmap[node]
                 p1, p2, linknode, copyfrom = pdata
                 # Don't follow renames (copyfrom).
diff --git a/hgext/remotefilelog/remotefilelogserver.py b/hgext/remotefilelog/remotefilelogserver.py
--- a/hgext/remotefilelog/remotefilelogserver.py
+++ b/hgext/remotefilelog/remotefilelogserver.py
@@ -22,6 +22,7 @@ from mercurial import (
     error,
     extensions,
     match,
+    pycompat,
     store,
     streamclone,
     util,
@@ -417,7 +418,7 @@ def gcserver(ui, repo):
     cachepath = repo.vfs.join(b"remotefilelogcache")
     for head in heads:
         mf = repo[head].manifest()
-        for filename, filenode in mf.iteritems():
+        for filename, filenode in pycompat.iteritems(mf):
             filecachepath = os.path.join(cachepath, filename, hex(filenode))
             neededfiles.add(filecachepath)
 
diff --git a/hgext/remotefilelog/repack.py b/hgext/remotefilelog/repack.py
--- a/hgext/remotefilelog/repack.py
+++ b/hgext/remotefilelog/repack.py
@@ -491,12 +491,12 @@ def keepset(repo, keyfn, lastkeepkeys=No
         if type(m) is dict:
             # m is a result of diff of two manifests and is a dictionary that
             # maps filename to ((newnode, newflag), (oldnode, oldflag)) tuple
-            for filename, diff in m.iteritems():
+            for filename, diff in pycompat.iteritems(m):
                 if diff[0][0] is not None:
                     keepkeys.add(keyfn(filename, diff[0][0]))
         else:
             # m is a manifest object
-            for filename, filenode in m.iteritems():
+            for filename, filenode in pycompat.iteritems(m):
                 keepkeys.add(keyfn(filename, filenode))
 
     return keepkeys
@@ -606,7 +606,7 @@ class repacker(object):
         repackprogress = ui.makeprogress(
             _(b"repacking data"), unit=self.unit, total=len(byfile)
         )
-        for filename, entries in sorted(byfile.iteritems()):
+        for filename, entries in sorted(pycompat.iteritems(byfile)):
             repackprogress.update(count)
 
             ancestors = {}
@@ -760,7 +760,7 @@ class repacker(object):
         progress = ui.makeprogress(
             _(b"repacking history"), unit=self.unit, total=len(byfile)
         )
-        for filename, entries in sorted(byfile.iteritems()):
+        for filename, entries in sorted(pycompat.iteritems(byfile)):
             ancestors = {}
             nodes = list(node for node in entries)
 
diff --git a/hgext/remotefilelog/shallowrepo.py b/hgext/remotefilelog/shallowrepo.py
--- a/hgext/remotefilelog/shallowrepo.py
+++ b/hgext/remotefilelog/shallowrepo.py
@@ -15,6 +15,7 @@ from mercurial import (
     error,
     localrepo,
     match,
+    pycompat,
     scmutil,
     sparse,
     util,
@@ -271,7 +272,7 @@ def wraprepo(repo):
             mfrevlog = mfl.getstorage(b'')
             if base is not None:
                 mfdict = mfl[repo[base].manifestnode()].read()
-                skip = set(mfdict.iteritems())
+                skip = set(pycompat.iteritems(mfdict))
             else:
                 skip = set()
 
@@ -301,7 +302,7 @@ def wraprepo(repo):
                 else:
                     mfdict = mfl[mfnode].read()
 
-                diff = mfdict.iteritems()
+                diff = pycompat.iteritems(mfdict)
                 if pats:
                     diff = (pf for pf in diff if m(pf[0]))
                 if sparsematch:
diff --git a/hgext/remotefilelog/shallowutil.py b/hgext/remotefilelog/shallowutil.py
--- a/hgext/remotefilelog/shallowutil.py
+++ b/hgext/remotefilelog/shallowutil.py
@@ -103,7 +103,7 @@ def sumdicts(*dicts):
     """
     result = collections.defaultdict(lambda: 0)
     for dict in dicts:
-        for k, v in dict.iteritems():
+        for k, v in pycompat.iteritems(dict):
             result[k] += v
     return result
 
@@ -111,7 +111,7 @@ def sumdicts(*dicts):
 def prefixkeys(dict, prefix):
     """Returns ``dict`` with ``prefix`` prepended to all its keys."""
     result = {}
-    for k, v in dict.iteritems():
+    for k, v in pycompat.iteritems(dict):
         result[prefix + k] = v
     return result
 
@@ -160,7 +160,7 @@ def _buildpackmeta(metadict):
     length limit is exceeded
     """
     metabuf = b''
-    for k, v in sorted((metadict or {}).iteritems()):
+    for k, v in sorted(pycompat.iteritems((metadict or {}))):
         if len(k) != 1:
             raise error.ProgrammingError(b'packmeta: illegal key: %s' % k)
         if len(v) > 0xFFFE:
@@ -188,7 +188,7 @@ def buildpackmeta(metadict):
     and METAKEYFLAG will be dropped if its value is 0.
     """
     newmeta = {}
-    for k, v in (metadict or {}).iteritems():
+    for k, v in pycompat.iteritems(metadict or {}):
         expectedtype = _metaitemtypes.get(k, (bytes,))
         if not isinstance(v, expectedtype):
             raise error.ProgrammingError(b'packmeta: wrong type of key %s' % k)
@@ -209,7 +209,7 @@ def parsepackmeta(metabuf):
     integers.
     """
     metadict = _parsepackmeta(metabuf)
-    for k, v in metadict.iteritems():
+    for k, v in pycompat.iteritems(metadict):
         if k in _metaitemtypes and int in _metaitemtypes[k]:
             metadict[k] = bin2int(v)
     return metadict
diff --git a/hgext/remotenames.py b/hgext/remotenames.py
--- a/hgext/remotenames.py
+++ b/hgext/remotenames.py
@@ -165,7 +165,7 @@ class lazyremotenamedict(mutablemapping)
         if not self.loaded:
             self._load()
 
-        for k, vtup in self.potentialentries.iteritems():
+        for k, vtup in pycompat.iteritems(self.potentialentries):
             yield (k, [bin(vtup[0])])
 
     items = iteritems
@@ -202,7 +202,7 @@ class remotenames(object):
         if not self._nodetobmarks:
             bmarktonodes = self.bmarktonodes()
             self._nodetobmarks = {}
-            for name, node in bmarktonodes.iteritems():
+            for name, node in pycompat.iteritems(bmarktonodes):
                 self._nodetobmarks.setdefault(node[0], []).append(name)
         return self._nodetobmarks
 
@@ -213,7 +213,7 @@ class remotenames(object):
         if not self._nodetobranch:
             branchtonodes = self.branchtonodes()
             self._nodetobranch = {}
-            for name, nodes in branchtonodes.iteritems():
+            for name, nodes in pycompat.iteritems(branchtonodes):
                 for node in nodes:
                     self._nodetobranch.setdefault(node, []).append(name)
         return self._nodetobranch
@@ -223,7 +223,7 @@ class remotenames(object):
             marktonodes = self.bmarktonodes()
             self._hoisttonodes = {}
             hoist += b'/'
-            for name, node in marktonodes.iteritems():
+            for name, node in pycompat.iteritems(marktonodes):
                 if name.startswith(hoist):
                     name = name[len(hoist) :]
                     self._hoisttonodes[name] = node
@@ -234,7 +234,7 @@ class remotenames(object):
             marktonodes = self.bmarktonodes()
             self._nodetohoists = {}
             hoist += b'/'
-            for name, node in marktonodes.iteritems():
+            for name, node in pycompat.iteritems(marktonodes):
                 if name.startswith(hoist):
                     name = name[len(hoist) :]
                     self._nodetohoists.setdefault(node[0], []).append(name)
diff --git a/hgext/strip.py b/hgext/strip.py
--- a/hgext/strip.py
+++ b/hgext/strip.py
@@ -206,7 +206,7 @@ def stripcmd(ui, repo, *revs, **opts):
             # a revision we have to only delete the bookmark and not strip
             # anything. revsets cannot detect that case.
             nodetobookmarks = {}
-            for mark, node in repomarks.iteritems():
+            for mark, node in pycompat.iteritems(repomarks):
                 nodetobookmarks.setdefault(node, []).append(mark)
             for marks in nodetobookmarks.values():
                 if bookmarks.issuperset(marks):
diff --git a/hgext/uncommit.py b/hgext/uncommit.py
--- a/hgext/uncommit.py
+++ b/hgext/uncommit.py
@@ -78,7 +78,9 @@ def _commitfiltered(
     files = initialfiles - exclude
     # Filter copies
     copied = copiesmod.pathcopies(base, ctx)
-    copied = dict((dst, src) for dst, src in copied.iteritems() if dst in files)
+    copied = dict(
+        (dst, src) for dst, src in pycompat.iteritems(copied) if dst in files
+    )
 
     def filectxfn(repo, memctx, path, contentctx=ctx, redirect=()):
         if path not in contentctx:
diff --git a/hgext/win32text.py b/hgext/win32text.py
--- a/hgext/win32text.py
+++ b/hgext/win32text.py
@@ -209,7 +209,7 @@ def forbidcr(ui, repo, hooktype, node, *
 def reposetup(ui, repo):
     if not repo.local():
         return
-    for name, fn in _filters.iteritems():
+    for name, fn in pycompat.iteritems(_filters):
         repo.adddatafilter(name, fn)
 
 
diff --git a/mercurial/__init__.py b/mercurial/__init__.py
--- a/mercurial/__init__.py
+++ b/mercurial/__init__.py
@@ -31,7 +31,7 @@ if sys.version_info[0] >= 3:
 
         def find_spec(self, fullname, path, target=None):
             # Only handle Mercurial-related modules.
-            if not fullname.startswith(('mercurial.', 'hgext.')):
+            if not fullname.startswith('mercurial.'):
                 return None
             # don't try to parse binary
             if fullname.startswith('mercurial.cext.'):
@@ -46,9 +46,6 @@ if sys.version_info[0] >= 3:
             # don't try and mangle it
             if fullname.startswith('mercurial.rustext'):
                 return None
-            # pywatchman is already dual-version clean, don't try and mangle it
-            if fullname.startswith('hgext.fsmonitor.pywatchman'):
-                return None
 
             # Try to find the module using other registered finders.
             spec = None
@@ -131,7 +128,7 @@ if sys.version_info[0] >= 3:
     # ``replacetoken`` or any mechanism that changes semantics of module
     # loading is changed. Otherwise cached bytecode may get loaded without
     # the new transformation mechanisms applied.
-    BYTECODEHEADER = b'HG\x00\x15'
+    BYTECODEHEADER = b'HG\x00\x16'
 
     class hgloader(importlib.machinery.SourceFileLoader):
         """Custom module loader that transforms source code.
diff --git a/mercurial/pycompat.py b/mercurial/pycompat.py
--- a/mercurial/pycompat.py
+++ b/mercurial/pycompat.py
@@ -337,6 +337,7 @@ if ispy3:
         ret = shlex.split(s.decode('latin-1'), comments, posix)
         return [a.encode('latin-1') for a in ret]
 
+    iteritems = lambda x: x.items()
     itervalues = lambda x: x.values()
 
 else:
@@ -414,6 +415,7 @@ else:
     ziplist = zip
     rawinput = raw_input
     getargspec = inspect.getargspec
+    iteritems = lambda x: x.iteritems()
     itervalues = lambda x: x.itervalues()
 
 isjython = sysplatform.startswith(b'java')