def test_multilineRemoveDirectoryResponse(self):
        """
        If the server returns multiple response lines, the L{Deferred} returned
        by L{ftp.FTPClient.removeDirectory} is still fired with a true value
         if the ultimate response code is 250.
        """
        self._testLogin()
        d = self.client.removeDirectory("/tmp/test")
        self.client.lineReceived(b'250-perhaps a progress report')
        self.client.lineReceived(b'250 okay')
        return d.addCallback(self.assertTrue)

        If the server returns multiple response lines, the L{Deferred} returned
        by L{ftp.FTPClient.removeDirectory} is still fired with a true value
         if the ultimate response code is 250.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_ftp.py