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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_simple_fault_geometry_3D(w, src):
 """ Builds a 3D polygon from a node instance """

    assert "simpleFaultSource" in src.tag
    geometry_node = src.nodes[get_taglist(src).index("simpleFaultGeometry")]
    fault_attrs = parse_simple_fault_geometry(geometry_node)
    build_polygon_from_fault_attrs(w, fault_attrs)