Fix regex so that it works with Python 3.6.

See <https://docs.python.org/3/library/re.html#re.LOCALE>.

Copied from upstream bug report:
https://bugs.launchpad.net/python-mox3/+bug/1665266

From 05064cdb6ea7a16450c6beae2b6f7c6074212a69 Mon Sep 17 00:00:00 2001
From: Zac Medico <zmedico@gentoo.org>
Date: Thu, 16 Feb 2017 00:24:10 -0800
Subject: [PATCH] RegexTest: python3.6 compatibility

These fixes are backward-compatible with older python versions:

* raw strings fix invalid escape sequences
* flags=8 fixes ValueError: cannot use LOCALE flag with a str pattern
---
 mox3/tests/test_mox.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mox3/tests/test_mox.py b/mox3/tests/test_mox.py
index 15ac565..3a1af17 100644
--- a/mox3/tests/test_mox.py
+++ b/mox3/tests/test_mox.py
@@ -312,12 +312,12 @@ class RegexTest(testtools.TestCase):
     def testReprWithoutFlags(self):
         """repr should return the regular expression pattern."""
         self.assertTrue(
-            repr(mox.Regex(r"a\s+b")) == "<regular expression 'a\s+b'>")
+            repr(mox.Regex(r"a\s+b")) == r"<regular expression 'a\s+b'>")
 
     def testReprWithFlags(self):
         """repr should return the regular expression pattern and flags."""
-        self.assertTrue(repr(mox.Regex(r"a\s+b", flags=4)) ==
-                        "<regular expression 'a\s+b', flags=4>")
+        self.assertTrue(repr(mox.Regex(r"a\s+b", flags=8)) ==
+                        r"<regular expression 'a\s+b', flags=8>")
 
 
 class IsTest(testtools.TestCase):
-- 
2.10.2

get' action='/guix/log/gnu/services/science.scm'>
<input type='hidden' name='id' value='6e20d190dccccbce33750cbdbe4a95f95bf8d87f'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=6e20d190dccccbce33750cbdbe4a95f95bf8d87f'>root</a>/<a href='/guix/log/gnu?id=6e20d190dccccbce33750cbdbe4a95f95bf8d87f'>gnu</a>/<a href='/guix/log/gnu/services?id=6e20d190dccccbce33750cbdbe4a95f95bf8d87f'>services</a>/<a href='/guix/log/gnu/services/science.scm?id=6e20d190dccccbce33750cbdbe4a95f95bf8d87f'>science.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/science.scm?id=6e20d190dccccbce33750cbdbe4a95f95bf8d87f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-12-09 12:55:02 +0200'>2020-12-09</span></td><td><a href='/guix/commit/gnu/services/science.scm?id=533935ccf71bef93f2f146fba1b2bb6402559965'>services: science.scm: Add missing copyright headers.</a><span class='msg-avail'>...<span class='msg-tooltip'>This module was always supposed to have the GPL3 header in place.
Follow-up to 8f19e63f760fe02f9969225da2f3f3c36801218f.

* gnu/services/science.scm: Add Copyright headers.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-06-28 14:03:03 +0300'>2020-06-28</span></td><td><a href='/guix/commit/gnu/services/science.scm?id=8f19e63f760fe02f9969225da2f3f3c36801218f'>services: Add rshiny service.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/science.scm: New file.
(&lt;rshiny-configuration&gt;): New record.
(rshiny-shepherd-service-type): New variable.
* doc/guix.texi (Miscellaneous Services): Document it.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
</span></span></td><td>Efraim Flashner</td></tr>