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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 set_area_geometry(w, src):
 """ Set area polygon as shapefile geometry """

    assert "areaSource" in src.tag
    geometry_node = src.nodes[get_taglist(src).index("areaGeometry")]
    area_attrs = parse_area_geometry(geometry_node)
    w.poly(parts=[area_attrs["polygon"].tolist()])