def keep_only_arrivals(data):
    """Remove departure events and rename arrival columns."""
    departure_cols = [
        "departure_time_planned",
        "departure_time_real",
        "departure_time_status",
    ]
    data = data.drop(departure_cols, axis=1)

    # Rename arrivals as events
    data = data.dropna(subset=["arrival_time_planned"], axis=0).rename(
        mapper={
            "arrival_time_planned": "event_time_planned",
            "arrival_time_real": "event_time_real",
            "arrival_time_status": "event_time_status",
        },
        axis=1,
    )

    return data