Fix a weird use of try/finally to close a file.

(There are more places that don't close 'f' at all if an error occurs,
but none have a bogus try/finally pattern.)

Lib/test/test_mmap.py

@@ -29,6 +29,7 @@ class MmapTests(unittest.TestCase):
             f.write(b'\0'* (PAGESIZE-3) )
             f.flush()
             m = mmap.mmap(f.fileno(), 2 * PAGESIZE)
+        finally:
             f.close()
 
         # Simple sanity checks
@@ -97,19 +98,15 @@ class MmapTests(unittest.TestCase):
             # Check that the underlying file is truncated too
             # (bug #728515)
             f = open(TESTFN)
+            try:
                 f.seek(0, 2)
                 self.assertEqual(f.tell(), 512)
+            finally:
                 f.close()
             self.assertEqual(m.size(), 512)
 
         m.close()
 
-        finally:
-            try:
-                f.close()
-            except OSError:
-                pass
-
     def test_access_parameter(self):
         # Test for "access" keyword parameter
         mapsize = 10