One less test failure: deleted the local test variable to prevent a test-run error.

Cherry-pick from: 'f8a5be7e'

Now at--

    Ran 159 tests in 0.738s
    FAILED (failures=18)

tests/test_spec.py

@@ -71,6 +71,8 @@ for spec in specs:
     for test in yaml.load(open(spec))['tests']:
         test = buildTest(test, file_name)
         setattr(MustacheSpec, test.__name__, test)
+        # Prevent this variable from being interpreted as another test.
+        del(test)
 
 if __name__ == '__main__':
     unittest.main()