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.
'>root</a>/<a href='/guix/log/po?id=d762e1c88c7a65417fed6f58a43bd312dc28ddcd'>po</a>/<a href='/guix/log/po/packages?id=d762e1c88c7a65417fed6f58a43bd312dc28ddcd'>packages</a>/<a href='/guix/log/po/packages/fa.po?id=d762e1c88c7a65417fed6f58a43bd312dc28ddcd'>fa.po</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/po/packages/fa.po?id=d762e1c88c7a65417fed6f58a43bd312dc28ddcd&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-04-02 18:42:36 +0200'>2022-04-02</span></td><td><a href='/guix/commit/po/packages/fa.po?id=8a208df17fe81fbf34f5a86cc52bb0b8e33c7b96'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fi.po: New file.
* po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-04-18 13:18:17 +0200'>2021-04-18</span></td><td><a href='/guix/commit/po/packages/fa.po?id=43fb84da6749a78d12ac0f13db4cecb435de7903'>nls: Add Persian translation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fa.po: New file.
* po/packages/LINGUAS: Add 'fa'.
* po/doc/guix-cookbook.fa.po: New file.
* po/doc/guix-manual.fa.po: New file.
* po/doc/local.mk (DOC_PO_FILES, DOC_COOKBOOK_PO_FILES): Add them.
* doc/local.mk (info_TEXINFOS): Add them.
</span></span></td><td>Julien Lepiller</td></tr>