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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 build_simple_fault_geometry(fault_source):
 """ Returns the simple fault source geometry as a Node :param fault_source: Simple fault source model as an instance of the :class: `openquake.hazardlib.source.simple_fault.SimpleFaultSource` :returns: Instance of :class:`openquake.baselib.node.Node` """

    linestring_node = build_linestring_node(fault_source.fault_trace,
                                            with_depth=False)
    dip_node = Node("dip", text=fault_source.dip)
    upper_depth_node = Node(
        "upperSeismoDepth", text=fault_source.upper_seismogenic_depth)
    lower_depth_node = Node(
        "lowerSeismoDepth", text=fault_source.lower_seismogenic_depth)
    return Node("simpleFaultGeometry",
                nodes=[linestring_node, dip_node, upper_depth_node,
                       lower_depth_node])