def METHOD_NAME(sources_meta_df: pd.DataFrame) -> Optional[Source]:
    if sources_meta_df.empty:
        return None
    sources = sources_meta_df.set_index(0).T.to_dict(orient="records")
    if not sources:
        return None
    assert len(sources) == 1, "Only one source is supported for now"
    source = sources[0]
    if pd.isnull(source.get("date_accessed")):
        source.pop("date_accessed")
    if pd.isnull(source.get("publication_year")):
        source.pop("publication_year")
    # publisher_source is not used anymore
    source.pop("publisher_source", None)
    # short_name is not used anymore
    source.pop("short_name", None)
    return Source(**source)