Add import_function method to test.test_support, and modify a number of
tests that expect to be skipped if imports fail or functions don't
exist to use import_function and import_module.  The ultimate goal is
to change regrtest to not skip automatically on ImportError.  Checking
in now to make sure the buldbots don't show any errors on platforms
I can't direct test on.
diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index 31daa8d..2dd76ad 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -1,8 +1,9 @@
-from test.test_support import TESTFN, run_unittest
-import mmap
+from test.test_support import TESTFN, run_unittest, import_module
 import unittest
 import os, re
 
+mmap = import_module('mmap')
+
 PAGESIZE = mmap.PAGESIZE
 
 class MmapTests(unittest.TestCase):