def _get_works(df, run, project, GEN=None):
    """ Get set of work values from a dataframe

    Parameters
    ----------
    df : pandas.DataFrame
        Information generated from folding at home
    run : str
        run to collect data for (i.e. 'RUN0')
    project : str
        project to collect data for (i.e. 'PROJ13420')
    GEN : str, optional default=None
        if provided, will only return work values from a given run, (i.e. 'GEN0'), otherwise all generations are returned

    Returns
    -------
    list, list
        Returns lists for forwards and backwards works

    """
    works = df[df["RUN"] == run]

    if GEN:
        works = works[works["GEN"] == GEN]

    f = works[works["PROJ"] == project].forward_work
    r = works[works["PROJ"] == project].reverse_work
    return f, r