Since feedparser messes with Python’s internals by assigning
to __code__ it needs to import SGMLParseError too. It also
expects SGMLParseError, which was turned into AssertionError by
https://github.com/python/cpython/commit/e34bbfd61f405eef89e8aa50672b0b25022de320

--- feedparser-6.0.10/feedparser/sgml.py.orig	2023-03-18 09:24:50.976316932 +0100
+++ feedparser-6.0.10/feedparser/sgml.py	2023-03-18 09:26:32.971928811 +0100
@@ -28,6 +28,7 @@
 import re
 
 import sgmllib
+from sgmllib import SGMLParseError
 
 __all__ = [
     'sgmllib',
@@ -41,6 +42,7 @@
     'shorttagopen',
     'starttagopen',
     'endbracket',
+    'SGMLParseError',
 ]
 
 # sgmllib defines a number of module-level regular expressions that are
--- feedparser-6.0.10/feedparser/html.py.orig	2023-03-18 09:32:03.647114745 +0100
+++ feedparser-6.0.10/feedparser/html.py	2023-03-18 09:46:05.021142671 +0100
@@ -349,7 +349,7 @@
 
         try:
             return sgmllib.SGMLParser.parse_declaration(self, i)
-        except sgmllib.SGMLParseError:
+        except AssertionError:
             # Escape the doctype declaration and continue parsing.
             self.handle_data('<')
             return i+1
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<tr><td><span title='2024-10-05 23:42:40 +0800'>2024-10-05</span></td><td><a href='/guix/commit/gnu/packages/tmux.scm?id=f2470fcb5ed1005d990fdcf65458dccf3f895c34'>gnu: tmux: Update to 3.5a.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/tmux.scm (tmux): Update to 3.5a.

Change-Id: I1e92cfcdb374f5a0131354900289766cbdf431e7
Signed-off-by: Zheng Junjie &lt;zhengjunjie@iscas.ac.cn&gt;
</span></span></td><td>Ashish SHUKLA via Guix-patches via</td></tr>
<tr><td><span title='2024-09-27 19:21:15 +0800'>2024-09-27</span></td><td><a href='/guix/commit/gnu/packages/tmux.scm?id=13b2b983ee2189493dc4f86670c1c13daa0c6bc6'>gnu: tmux: Build from git.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/tmux.scm (tmux)[source]: Switch to git-fetch, and use
git-file-name.
[native-inputs]: Add autoconf, automake and pkg-config.

Change-Id: If56abbb76f3b00193bbd27c236a9f82c4f0eb3cb
</span></span></td><td>Zheng Junjie</td></tr>
<tr><td><span title='2024-09-27 19:11:19 +0800'>2024-09-27</span></td><td><a href='/guix/commit/gnu/packages/tmux.scm?id=d4542b430f807c6de64602e25eebd3cd5aee924f'>gnu: tmux: Update to 3.5.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/tmux (tmux): Update to 3.5.

Change-Id: Ia1f4e6e6d17d8ce76345f06f87247a13b4b5a7bb
Signed-off-by: Zheng Junjie &lt;zhengjunjie@iscas.ac.cn&gt;
</span></span></td><td>Ashish SHUKLA via Guix-patches via</td></tr>
<tr><td><span title='2024-05-12 18:31:25 +0100'>2024-05-12</span></td><td><a href='/guix/commit/gnu/packages/tmux.scm?id=0dac1307ccc9a04df49080f3c76b1018268d7d68'>gnu: tmux: Update to 3.4.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/tmux.scm (tmux): Update to 3.4.
[native-inputs]: Add bison.

Reviewed-by: Dale Mellor &lt;guix-devel-0brg6a@rdmp.org&gt;
Signed-off-by: Christopher Baines &lt;mail@cbaines.net&gt;
Change-Id: I549010a3cf492ffe9cdc9df25b2b4a93c60c6ae1
</span></span></td><td>Ashish SHUKLA</td></tr>