lib2to3 tests: Don't use deprecated API, switch to assertRegex()

Lib/lib2to3/tests/test_main.py

@@ -94,7 +94,7 @@ class TestMain(unittest.TestCase):
             self.assertIn("Writing converted %s to %s" % (
                     os.path.join(self.py2_src_dir, name),
                     os.path.join(self.py3_dest_dir, name+suffix)), stderr)
-        self.assertRegexpMatches(stderr, r"No changes to .*/__init__\.py")
+        self.assertRegex(stderr, r"No changes to .*/__init__\.py")
         self.assertNotRegex(stderr, r"No changes to .*/trivial\.py")
 
     def test_filename_changing_on_output_two_files(self):

Lib/lib2to3/tests/test_refactor.py

@@ -230,7 +230,7 @@ from __future__ import print_function"""
                 os.sep, os.path.basename(test_file))
         for message in debug_messages:
             if "Not writing changes" in message:
-                self.assertRegexpMatches(message, message_regex)
+                self.assertRegex(message, message_regex)
                 break
         else:
             self.fail("%r not matched in %r" % (message_regex, debug_messages))