Fix build with Python 3 scons.

Patch taken from Arch Linux:
https://github.com/archlinux/svntogit-packages/blob/packages/serf/trunk/scons-python3.patch

--- serf-1.3.9/SConstruct.orig	2019-07-26 17:49:30.910189251 +0000
+++ serf-1.3.9/SConstruct	2019-07-26 17:49:54.073821735 +0000
@@ -163,9 +163,9 @@
               suffix='.def', src_suffix='.h')
   })
 
-match = re.search('SERF_MAJOR_VERSION ([0-9]+).*'
-                  'SERF_MINOR_VERSION ([0-9]+).*'
-                  'SERF_PATCH_VERSION ([0-9]+)',
+match = re.search(b'SERF_MAJOR_VERSION ([0-9]+).*'
+                  b'SERF_MINOR_VERSION ([0-9]+).*'
+                  b'SERF_PATCH_VERSION ([0-9]+)',
                   env.File('serf.h').get_contents(),
                   re.DOTALL)
 MAJOR, MINOR, PATCH = [int(x) for x in match.groups()]
@@ -183,7 +183,7 @@
 
 unknown = opts.UnknownVariables()
 if unknown:
-  print 'Warning: Used unknown variables:', ', '.join(unknown.keys())
+  print ('Warning: Used unknown variables:', ', '.join(unknown.keys()))
 
 apr = str(env['APR'])
 apu = str(env['APU'])
>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>refs</a><a class='active' href='/guix/log/gnu/services/mcron.scm'>log</a><a href='/guix/tree/gnu/services/mcron.scm?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>tree</a><a href='/guix/commit/gnu/services/mcron.scm?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>commit</a><a href='/guix/diff/gnu/services/mcron.scm?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/services/mcron.scm'>
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<div class='path'>path: <a href='/guix/log/?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>root</a>/<a href='/guix/log/gnu?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>gnu</a>/<a href='/guix/log/gnu/services?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>services</a>/<a href='/guix/log/gnu/services/mcron.scm?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1'>mcron.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/services/mcron.scm?id=832ef198f7e423e0fdff7fe7c5558ff13d1f20c1&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-08-28 16:37:32 +0200'>2024-08-28</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=ebe00a20e2aea189b5c59d0550fd75ab58443ff8'>services: mcron: Fix home version not respecting user PATH variable.</a><span class='msg-avail'>...<span class='msg-tooltip'>Without this fix, deploying `home-mcron-service-type' will strip user's PATH
variable from it's environment. This means that, programs such as `notmuch',
which use hooks which usually invoke `notmuch' from path, would need to be
updated with full paths; which makes it very inconvenient to use.

* gnu/services/mcron.scm (mcron-shepherd-services): respect user PATH variable.

Change-Id: I104aa0a818ad6c3266b2b8f73a9609bfb36e314d
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Sergio Pastor Pérez</td></tr>
<tr><td><span title='2023-10-05 23:14:55 +0200'>2023-10-05</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=a0818d0236056dae043f9d1997b0c45ee40bbe26'>services: mcron: Hide ‘mkdir-p’ from (shepherd support).</a><span class='msg-avail'>...<span class='msg-tooltip'>This a avoids a Guile warning about the name collision with (guix build
utils).  The warning was introduced by commit
e0e85f2b2396c69d078caad9bd8e1a0fddf33a4a.

* gnu/services/mcron.scm (mcron-shepherd-services): Hide ‘mkdir-p’.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-10-02 17:17:07 +0200'>2023-10-02</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=e0e85f2b2396c69d078caad9bd8e1a0fddf33a4a'>services: mcron: Do not #:select ‘%user-log-dir’.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/mcron.scm (mcron-shepherd-services): Do not #:select
‘%user-log-dir’ from (shepherd support) since it’s missing in the
Shepherd 0.8, which is still used on GNU/Hurd.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-08-22 21:37:41 +0800'>2023-08-22</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=0c4fb8f43f8aba2dcabe1bc97a8f6d8d41057704'>services: mcron: Use (shepherd support) module unconditionally.</a><span class='msg-avail'>...<span class='msg-tooltip'>This fixes a issue introduced in the previous commit 552d0703776c (services:
mcron: Add module for %user-log-dir.)  which made the expression invalid when
using a '() module for the system service.

* gnu/services/mcron.scm (mcron-shepherd-services)[modules]: Use
(shepherd support) unconditionally.
</span></span></td><td>Hilton Chain</td></tr>
<tr><td><span title='2023-08-22 20:18:34 +0800'>2023-08-22</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=552d0703776c532f25498d5cb852c3c497cb9252'>services: mcron: Add module for %user-log-dir.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/mcron.scm (mcron-shepherd-services)[modules]: Add
(shepherd support) for home service.
</span></span></td><td>Hilton Chain</td></tr>
<tr><td><span title='2023-08-20 22:48:47 +0200'>2023-08-20</span></td><td><a href='/guix/commit/gnu/services/mcron.scm?id=1c30d5a6bfc5d48137f4bdcc271189a06fdc6ed3'>home: services: mcron: Define as a mapping of the system service.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/mcron.scm (list-of-gexps?): Remove.
(&lt;mcron-configuration&gt;): Rewrite using 'define-record-type*'.
[home-service?]: New field.
[log-file]: Make thunked and changed default value.
(mcron-shepherd-services): Honor 'home-service?' and remove use of
'maybe-value-set?'.
(mcron-service-type): Inherit 'home-service?' from CONFIG.
(generate-doc): Remove.
* gnu/home/services/mcron.scm (list-of-gexp?)
(&lt;home-mcron-configuration&gt;, job-files, shepherd-schedule-action)
(home-mcron-shepherd-services, home-mcron-profile)
(home-mcron-extend, generate-doc): Remove.
(home-mcron-configuration): Turn into a macro.
(home-mcron-service-type): Define in terms of
'system-&gt;home-service-type'.
&lt;top level&gt;: Add service type mapping.
</span></span></td><td>Ludovic Courtès</td></tr>