diff -Nru atropos-1.1.29+dfsg/debian/changelog atropos-1.1.29+dfsg/debian/changelog
--- atropos-1.1.29+dfsg/debian/changelog	2020-12-09 21:29:55.000000000 +0000
+++ atropos-1.1.29+dfsg/debian/changelog	2022-01-28 13:11:11.000000000 +0000
@@ -1,3 +1,15 @@
+atropos (1.1.29+dfsg-1ubuntu1) jammy; urgency=medium
+
+  * Python 3.10 compatibility: import from collections.abc
+
+ -- Graham Inggs <ginggs@ubuntu.com>  Fri, 28 Jan 2022 13:11:11 +0000
+
+atropos (1.1.29+dfsg-1build1) jammy; urgency=medium
+
+  * No-change rebuild with Python 3.10 as default version
+
+ -- Graham Inggs <ginggs@ubuntu.com>  Thu, 13 Jan 2022 19:03:12 +0000
+
 atropos (1.1.29+dfsg-1) unstable; urgency=medium
 
   * Team upload.
diff -Nru atropos-1.1.29+dfsg/debian/control atropos-1.1.29+dfsg/debian/control
--- atropos-1.1.29+dfsg/debian/control	2020-12-09 17:34:30.000000000 +0000
+++ atropos-1.1.29+dfsg/debian/control	2022-01-28 12:39:41.000000000 +0000
@@ -1,5 +1,6 @@
 Source: atropos
-Maintainer: Debian Med Packaging Team <debian-med-packaging@lists.alioth.debian.org>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+XSBC-Original-Maintainer: Debian Med Packaging Team <debian-med-packaging@lists.alioth.debian.org>
 Uploaders: Andreas Tille <tille@debian.org>
 Section: science
 Priority: optional
diff -Nru atropos-1.1.29+dfsg/debian/patches/python3.10.patch atropos-1.1.29+dfsg/debian/patches/python3.10.patch
--- atropos-1.1.29+dfsg/debian/patches/python3.10.patch	1970-01-01 00:00:00.000000000 +0000
+++ atropos-1.1.29+dfsg/debian/patches/python3.10.patch	2022-01-28 12:38:53.000000000 +0000
@@ -0,0 +1,36 @@
+Description: Python 3.10 compatibility
+Author: Graham Inggs <ginggs@debian.org>
+Last-Update: 2022-01-28
+
+--- a/atropos/util/__init__.py
++++ b/atropos/util/__init__.py
+@@ -1,6 +1,7 @@
+ """Widely useful utility methods.
+ """
+-from collections import OrderedDict, Iterable, Sequence
++from collections import OrderedDict
++from collections.abc import Iterable, Sequence
+ from datetime import datetime
+ import errno
+ import functools
+--- a/atropos/commands/base.py
++++ b/atropos/commands/base.py
+@@ -1,6 +1,6 @@
+ """Common classes/functions used in commands.
+ """
+-from collections import Sequence
++from collections.abc import Sequence
+ import copy
+ import platform
+ import sys
+--- a/atropos/commands/trim/__init__.py
++++ b/atropos/commands/trim/__init__.py
+@@ -1,6 +1,7 @@
+ """Implementation of the 'trim' command.
+ """
+-from collections import Sequence, defaultdict
++from collections import defaultdict
++from collections.abc import Sequence
+ import logging
+ import os
+ import sys
diff -Nru atropos-1.1.29+dfsg/debian/patches/series atropos-1.1.29+dfsg/debian/patches/series
--- atropos-1.1.29+dfsg/debian/patches/series	1970-01-01 00:00:00.000000000 +0000
+++ atropos-1.1.29+dfsg/debian/patches/series	2022-01-28 12:38:06.000000000 +0000
@@ -0,0 +1 @@
+python3.10.patch