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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 get_nodes(self):
 """Get the tree nodes as list. Returns: list: A 2d-list holding the grown nodes coordinates as tupel for every age. Example: [ [(10, 40)], [(20, 80), (100, 30)], ] """

        nodes = []
        for age, level in enumerate(self.nodes):
            nodes.append([])
            for node in level:
                nodes[age].append(node.get_tuple())
        return nodes