bpo-35767: Fix unittest.loader to allow partials as test_functions (GH-11600) (#11662)

(cherry picked from commit fd628cf5adaeee73eab579393cdff71c8f70cdf2)

Co-authored-by: Jason Fried <me@jasonfried.info>
diff --git a/Lib/unittest/loader.py b/Lib/unittest/loader.py
index d936a96..ba7105e 100644
--- a/Lib/unittest/loader.py
+++ b/Lib/unittest/loader.py
@@ -229,7 +229,9 @@
             testFunc = getattr(testCaseClass, attrname)
             if not callable(testFunc):
                 return False
-            fullName = '%s.%s' % (testCaseClass.__module__, testFunc.__qualname__)
+            fullName = f'%s.%s.%s' % (
+                testCaseClass.__module__, testCaseClass.__qualname__, attrname
+            )
             return self.testNamePatterns is None or \
                 any(fnmatchcase(fullName, pattern) for pattern in self.testNamePatterns)
         testFnNames = list(filter(shouldIncludeMethod, dir(testCaseClass)))