def test_horizontalTabulationSet(self):
        """
        L{ServerProtocol.horizontalTabulationSet} writes the escape
        sequence ending in L{C1SevenBit.HTS}
        """
        self.protocol.horizontalTabulationSet()
        self.assertEqual(self.transport.value(),
                         self.ESC +
                         C1SevenBit.HTS.value)

        L{ServerProtocol.horizontalTabulationSet} writes the escape
        sequence ending in L{C1SevenBit.HTS}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_insults.py