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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 node_to_simple_fault_geometry(node):
 """ Reads a simple fault geometry node and returns an OpenQuake representation :returns: trace - Trace of fault as instance """

    assert "simpleFaultGeometry" in node.tag
    for subnode in node.nodes:
        if "LineString" in subnode.tag:
            trace = linestring_node_to_line(subnode, with_depth=False)
        elif "dip" in subnode.tag:
            dip = float(subnode.text)
        elif "upperSeismoDepth" in subnode.tag:
            upper_depth = float(subnode.text)
        elif "lowerSeismoDepth" in subnode.tag:
            lower_depth = float(subnode.text)
        else:
            # Redundent
            pass
    assert lower_depth > upper_depth
    return trace, dip, upper_depth, lower_depth