def test_allKeysInAllAuthorizedFilesForAuthorizedUser(self):
        """
        If the user is in the user database provided to
        L{checkers.UNIXAuthorizedKeysFiles}, an iterator with all the keys in
        C{~/.ssh/authorized_keys} and C{~/.ssh/authorized_keys2} is returned
        by L{checkers.UNIXAuthorizedKeysFiles.getAuthorizedKeys}.
        """
        self.sshDir.child('authorized_keys2').setContent(b'key 3')
        keydb = checkers.UNIXAuthorizedKeysFiles(self.userdb,
                                                 parseKey=lambda x: x)
        self.assertEqual(self.expectedKeys + [b'key 3'],
                         list(keydb.getAuthorizedKeys(b'alice')))

        If the user is in the user database provided to
        L{checkers.UNIXAuthorizedKeysFiles}, an iterator with all the keys in
        C{~/.ssh/authorized_keys} and C{~/.ssh/authorized_keys2} is returned
        by L{checkers.UNIXAuthorizedKeysFiles.getAuthorizedKeys}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_checkers.py