def METHOD_NAME(self):
    for module in dbm_iterator():
        # Check whether whichdb correctly guesses module name
        # for databases opened with "module" module.
        # Try with empty files first
        name = module.__name__
        if name == 'dbm.dumb':
            continue   # whichdb can't support dbm.dumb
        delete_files()
        f = module.open(_fname, 'c')
        f.close()
        self.assertEqual(name, self.dbm.whichdb(_fname))
        # Now add a key
        f = module.open(_fname, 'w')
        f[b"1"] = b"1"
        # and test that we can find it
        self.assertIn(b"1", f)
        # and read it
        self.assertTrue(f[b"1"] == b"1")
        f.close()
        self.assertEqual(name, self.dbm.whichdb(_fname))