def compute_center(
    feed: "Feed", num_busiest_stops: Optional[int] = None
) -> Tuple:
    """
    Return the centroid (WGS84 longitude-latitude pair) of the convex
    hull of the stops of the given Feed.
    If ``num_busiest_stops`` (integer) is given,
    then compute the ``num_busiest_stops`` busiest stops in the feed
    on the first Monday of the feed and return the mean of the
    longitudes and the mean of the latitudes of these stops,
    respectively.
    """
    s = feed.stops.copy()
    if num_busiest_stops is None:
        hull = compute_convex_hull(feed)
        lon, lat = list(hull.centroid.coords)[0]
    else:
        date = feed.get_first_week()[0]
        ss = feed.compute_stop_stats([date]).sort_values(
            "num_trips", ascending=False
        )
        if ss.stop_id.isnull().all():
            # No stats, which could happen with a crappy feed.
            # Fall back to all stops.
            hull = compute_convex_hull(feed)
            lon, lat = list(hull.centroid.coords)[0]
        else:
            f = ss.head(num_busiest_stops)
            f = s.merge(f)
            lon = f["stop_lon"].mean()
            lat = f["stop_lat"].mean()

    return lon, lat
Return the centroid (WGS84 longitude-latitude pair) of the convex
    hull of the stops of the given Feed.
    If ``num_busiest_stops`` (integer) is given,
    then compute the ``num_busiest_stops`` busiest stops in the feed
    on the first Monday of the feed and return the mean of the
    longitudes and the mean of the latitudes of these stops,
    respectively.