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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_node_positions(self):
 """ Computes nodes positions. Arranges nodes in a line starting at (x,y) = (0,0). Node radius is assumed to be equal to 0.5 units. Nodes are placed at integer locations. """

        xs = [0] * len(self.nodes)
        ys = [0] * len(self.nodes)
        for i, _ in enumerate(self.nodes[1:], start=1):
            prev_r = self.node_sizes[i - 1] / 2
            curr_r = self.node_sizes[i] / 2
            xs[i] = xs[i - 1] + prev_r + curr_r

        self.node_coords = {"x": xs, "y": ys}