def pipe_data_received(self, fd, data):
if fd == <NUM_LIT:2>:  <EOL><INDENT>self._on_stderr(data)<EOL><DEDENT>elif self._on_data:<EOL><INDENT>self._on_data(data)<EOL><DEDENT>else:<EOL><INDENT>self._queued_data.append(data)<EOL><DEDENT>
Used to signal `asyncio.SubprocessProtocol` of incoming data.