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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 selection(self):
 """A complete |Selection| object of all "supplying" and "routing" elements and required nodes. Selection("complete", nodes=("node_1123", "node_1125", "node_11269", "node_1129", "node_113", "node_outlet"), elements=("land_111", "land_1121", "land_1122", "land_1123", "land_1124", "land_1125", "land_11261", "land_11262", "land_11269", "land_1129", "land_113", "stream_1123", "stream_1125", "stream_11269", "stream_1129", "stream_113")) Besides the possible modifications on the names of the different nodes and elements, the name of the selection can be set differently: Selection("sel", """

        return selectiontools.Selection(
            self.selection_name, self.nodes, self.elements)