def METHOD_NAME(self):
    self.sock.buffer_writes = True
    ret = self.sock.send(bytearray(b'abc'))
    self.assertEqual(ret, 3)
    self.raw_sock.sendall.assert_not_called()
    self.sock.flush()
    self.raw_sock.sendall.assert_called_once_with(bytearray(b'abc'))