TestMIMEAudio.setUp(): Use the email package's copy of the audio test

file, needed because some binary distros (read RPMs) don't include the
test module in their standard Python package.  This eliminates an
external dependency and closes SF bug # 650441.

Lib/email/test/test_email.py

@@ -769,8 +769,13 @@ Blah blah blah
 # Test the basic MIMEAudio class
 class TestMIMEAudio(unittest.TestCase):
     def setUp(self):
-        # In Python, audiotest.au lives in Lib/test not Lib/test/data
-        fp = open(findfile('audiotest.au'), 'rb')
+        # Make sure we pick up the audiotest.au that lives in email/test/data.
+        # In Python, there's an audiotest.au living in Lib/test but that isn't
+        # included in some binary distros that don't include the test
+        # package.  The trailing empty string on the .join() is significant
+        # since findfile() will do a dirname().
+        datadir = os.path.join(os.path.dirname(landmark), 'data', '')
+        fp = open(findfile('audiotest.au', datadir), 'rb')
         try:
             self._audiodata = fp.read()
         finally: