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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_geostationary_mask(area):
 """Compute a mask of the earth's shape as seen by a geostationary satellite Args: area (pyresample.geometry.AreaDefinition) : Corresponding area definition Returns: Boolean mask, True inside the earth's shape, False outside. """

    # Compute projection coordinates at the earth's limb
    h = area.proj_dict['h']
    xmax, ymax = get_geostationary_angle_extent(area)
    xmax *= h
    ymax *= h

    # Compute projection coordinates at the centre of each pixel
    x, y = area.get_proj_coords_dask()

    # Compute mask of the earth's elliptical shape
    return ((x / xmax) ** 2 + (y / ymax) ** 2) <= 1