diff -r 2372284d9457 -r 687b865b95ad hgext/children.py
--- a/hgext/children.py	Sun Oct 06 09:45:02 2019 -0400
+++ b/hgext/children.py	Sun Oct 06 09:48:39 2019 -0400
@@ -33,14 +33,22 @@
 # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
 # be specifying the version(s) of Mercurial they are tested with, or
 # leave the attribute unspecified.
-testedwith = 'ships-with-hg-core'
+testedwith = b'ships-with-hg-core'
 
 
 @command(
-    'children',
-    [('r', 'rev', '.', _('show children of the specified revision'), _('REV')),]
+    b'children',
+    [
+        (
+            b'r',
+            b'rev',
+            b'.',
+            _(b'show children of the specified revision'),
+            _(b'REV'),
+        ),
+    ]
     + templateopts,
-    _('hg children [-r REV] [FILE]'),
+    _(b'hg children [-r REV] [FILE]'),
     helpcategory=command.CATEGORY_CHANGE_NAVIGATION,
     inferrepo=True,
 )
@@ -62,7 +70,7 @@
 
     """
     opts = pycompat.byteskwargs(opts)
-    rev = opts.get('rev')
+    rev = opts.get(b'rev')
     ctx = scmutil.revsingle(repo, rev)
     if file_:
         fctx = repo.filectx(file_, changeid=ctx.rev())