def unpickleStringO(val, sek):
    """
    Convert the output of L{pickleStringO} into an appropriate type for the
    current python version.  This may be called on Python 3 and will convert a
    cStringIO into an L{io.StringIO}.

    @param val: The content of the file.
    @type val: L{bytes}

    @param sek: The seek position of the file.
    @type sek: L{int}

    @return: a file-like object which you can write bytes to.
    @rtype: L{cStringIO.OutputType} on Python 2, L{io.StringIO} on Python 3.
    """
    x = _cStringIO()
    x.write(val)
    x.seek(sek)
    return x

    Convert the output of L{pickleStringO} into an appropriate type for the
    current python version.  This may be called on Python 3 and will convert a
    cStringIO into an L{io.StringIO}.

    @param val: The content of the file.
    @type val: L{bytes}

    @param sek: The seek position of the file.
    @type sek: L{int}

    @return: a file-like object which you can write bytes to.
    @rtype: L{cStringIO.OutputType} on Python 2, L{io.StringIO} on Python 3.
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/persisted/styles.py