def pipe(engine, format, data):
    args, _ = command(engine, format)

    try:
        proc = subprocess.Popen(args, stdin=subprocess.PIPE,
            stdout=subprocess.PIPE, startupinfo=STARTUPINFO)
    except OSError as e:
        if e.errno == errno.ENOENT:
            raise RuntimeError('failed to execute %r, '
                'make sure the Graphviz executables '
                'are on your systems\' path' % args)
        else:  # pragma: no cover
            raise

    outs, errs = proc.communicate(data)

    return outs
Return data piped through Graphviz engine into format.
dataset/ETHPy150Open xflr6/graphviz/graphviz/backend.py/pipe