def calc_contours(data, num_contours):
    """Get sets of contour points for numpy array `data`.
    `num_contours` specifies the number (int) of contours to make.
    Returns a list of numpy arrays of points--each array makes a polygon
    if plotted as such.
    """
    mn = np.nanmean(data)
    top = np.nanmax(data)
    levels = np.linspace(mn, top, num_contours)
    return get_contours(data, levels)
Get sets of contour points for numpy array `data`.
    `num_contours` specifies the number (int) of contours to make.
    Returns a list of numpy arrays of points--each array makes a polygon
    if plotted as such.