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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 compute_depth(self):
 """ Recursively computes true depth of the subtree. Should only be needed for debugging. Unless something is wrong, the depth field should reflect the correct depth of the subtree. """

        left_depth = self.left_node.compute_depth() if self.left_node else 0
        right_depth = self.right_node.compute_depth() if self.right_node else 0
        return 1 + max(left_depth, right_depth)