Combine the functionality of test_support.run_unittest()
and test_support.run_classtests() into run_unittest()
and use it wherever possible.

Also don't use "from test.test_support import ...", but
"from test import test_support" in a few spots.

From SF patch #662807.
diff --git a/Lib/test/test_getargs2.py b/Lib/test/test_getargs2.py
index aaa64e0..587fe1f 100644
--- a/Lib/test/test_getargs2.py
+++ b/Lib/test/test_getargs2.py
@@ -223,16 +223,14 @@
         self.failUnlessEqual(VERY_LARGE & ULLONG_MAX, getargs_K(VERY_LARGE))
 
 def test_main():
-    suite = unittest.TestSuite()
-    suite.addTest(unittest.makeSuite(Signed_TestCase))
-    suite.addTest(unittest.makeSuite(Unsigned_TestCase))
+    tests = [Signed_TestCase, Unsigned_TestCase]
     try:
         from _testcapi import getargs_L, getargs_K
     except ImportError:
         pass # PY_LONG_LONG not available
     else:
-        suite.addTest(unittest.makeSuite(LongLong_TestCase))
-    test_support.run_suite(suite)
+        tests.append(LongLong_TestCase)
+    test_support.run_unittest(*tests)
 
 if __name__ == "__main__":
     test_main()