def METHOD_NAME(pdict, a_ext):
    """Get the area definition for a geo-sat.
    Args:
        pdict: A dictionary containing common parameters:
            nlines: Number of lines in image
            ncols: Number of columns in image
            ssp_lon: Subsatellite point longitude (deg)
            a: Earth equatorial radius (m)
            b: Earth polar radius (m)
            h: Platform height (m)
            a_name: Area name
            a_desc: Area description
            p_id: Projection id
        a_ext: A four element tuple containing the area extent (scan angle)
               for the scene in radians
    Returns:
        a_def: An area definition for the scene
    .. note::
        The AreaDefinition `proj_id` attribute is being deprecated.
    """
    proj_dict = {'a': float(pdict['a']),
                 'b': float(pdict['b']),
                 'lon_0': float(pdict['ssp_lon']),
                 'h': float(pdict['h']),
                 'proj': 'geos',
                 'units': 'm'}
    a_def = geometry.AreaDefinition(
        pdict['a_name'],
        pdict['a_desc'],
        pdict['p_id'],
        proj_dict,
        int(pdict['ncols']),
        int(pdict['nlines']),
        a_ext)
    return a_def