Skip tests that fail with newer versions of Python.

Patch copied from Gentoo:

https://gitweb.gentoo.org/repo/gentoo.git/tree/dev-python/unittest2/files/unittest2-1.1.0-python3.5-test.patch

diff --git a/unittest2/test/test_loader.py b/unittest2/test/test_loader.py
index 683f662..347eea5 100644
--- a/unittest2/test/test_loader.py
+++ b/unittest2/test/test_loader.py
@@ -509,6 +509,7 @@ class Test_TestLoader(unittest2.TestCase):
     #
     # What happens when an impossible name is given, relative to the provided
     # `module`?
+    @unittest.skipIf(sys.version_info[:2] >= (3, 5), "python 3.5 has problems here")
     def test_loadTestsFromName__relative_malformed_name(self):
         loader = unittest.TestLoader()
 
@@ -811,6 +812,7 @@ class Test_TestLoader(unittest2.TestCase):
     # TestCase or TestSuite instance."
     #
     # What happens when presented with an impossible module name?
+    @unittest.skipIf(sys.version_info[:2] >= (3, 5), "python 3.5 has problems here")
     def test_loadTestsFromNames__malformed_name(self):
         loader = unittest2.TestLoader()
 
@@ -918,6 +920,7 @@ class Test_TestLoader(unittest2.TestCase):
     # "The method optionally resolves name relative to the given module"
     #
     # What happens when presented with an impossible attribute name?
+    @unittest.skipIf(sys.version_info[:2] >= (3, 5), "python 3.5 has problems here")
     def test_loadTestsFromNames__relative_malformed_name(self):
         loader = unittest.TestLoader()
 
diff --git a/unittest2/compatibility.py b/unittest2/compatibility.py
index 9e5f1a5..2d20c19 100644
--- a/unittest2/compatibility.py
+++ b/unittest2/compatibility.py
@@ -140,6 +140,6 @@ except ImportError:
 ###  ChainMap (helper for configparser and string.Template)
 ########################################################################
 
-class ChainMap(collections.MutableMapping):
+class ChainMap(collections.abc.MutableMapping):
     ''' A ChainMap groups multiple dicts (or other mappings) together
     to create a single, updateable view.
/log/?id=8b13984fac92f78ac1585e5b8ebbd34eec41f739'>root</a>/<a href='/guix/log/gnu?id=8b13984fac92f78ac1585e5b8ebbd34eec41f739'>gnu</a>/<a href='/guix/log/gnu/services?id=8b13984fac92f78ac1585e5b8ebbd34eec41f739'>services</a>/<a href='/guix/log/gnu/services/cuirass.scm?id=8b13984fac92f78ac1585e5b8ebbd34eec41f739'>cuirass.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/cuirass.scm?id=8b13984fac92f78ac1585e5b8ebbd34eec41f739&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-12-07 23:36:20 +0100'>2022-12-07</span></td><td><a href='/guix/commit/gnu/services/cuirass.scm?id=ac682963a385a44874d91052fd5845f2cc0e8f3e'>service: cuirass: Rotate remote server logs.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/cuirass.scm (cuirass-log-rotations): Add the remote
server log when it is used.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-12-07 23:36:19 +0100'>2022-12-07</span></td><td><a href='/guix/commit/gnu/services/cuirass.scm?id=ce1f5ff6cff2a3c820c4212ae8d4c4cfa5ae949c'>services: cuirass-remote-worker: Rotate logs.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/cuirass.scm (cuirass-remote-worker-log-rotations): New
procedure.
(cuirass-remote-worker-service-type): Use it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-12-02 00:02:12 +0100'>2022-12-02</span></td><td><a href='/guix/commit/gnu/services/cuirass.scm?id=7c1161dba4c8930d3a500a72ccaaaf50df73f466'>records: 'match-record' checks fields at macro-expansion time.</a><span class='msg-avail'>...<span class='msg-tooltip'>This allows 'match-record' to be more efficient (field offsets are
computed at compilation time) and to report unknown fields at
macro-expansion time.

* guix/records.scm (map-fields): New macro.
(define-record-type*)[rtd-identifier]: New procedure.
Define TYPE as a macro and use a separate identifier for the RTD.
(lookup-field, match-record-inner): New macros.
(match-record): Rewrite in terms of 'match-error-inner'.
* tests/records.scm ("match-record, simple")
("match-record, unknown field"): New tests.
* gnu/services/cuirass.scm (cuirass-shepherd-service): Rename 'log-file'
local variable to 'main-log-file'.
* gnu/services/getmail.scm (serialize-getmail-configuration-file): Move
after &lt;getmail-configuration-file&gt; definition.
</span></span></td><td>Ludovic Courtès</td></tr>