def plot(client, file_=None, dirname=None, driver=None):
    """Export a model plot.

    Args:
        client (obj):
            creopyson Client.
        `file_` (str, optional):
            Model name. Defaults is currently active model.
        dirname (str, optional):
            Destination directory.
            Defaults is Creo's current working directory.
        driver (str, optional):
            Driver export.
            Defaults is `POSTSCRIPT`.
            Valid values: POSTSCRIPT, JPEG, TIFF.

    Returns:
        dict:
            dirname (str): Directory of the output file
            filename (str): Name of the output file

    """
    data = {}
    if file_ is not None:
        data['file'] = file_
    else:
        active_file = client.file_get_active()
        if active_file is not None:
            data['file'] = active_file['file']
    if dirname:
        data['dirname'] = dirname
    if driver:
        data['driver'] = driver
    return client._creoson_post('interface', 'plot', data)
