code: def compute_node_positions(self):
          
          xs = []
          ys = []
          self.locs = dict()
  
          for node in self.nodes:
              x = self.graph.node[node][self.node_lon]
              y = self.graph.node[node][self.node_lat]
              xs.append(x)
              ys.append(y)
              self.locs[node] = (x, y)
  
          self.node_coords = {"x": xs, "y": ys}
docs: Extracts the node positions based on the specified longitude and
          latitude keyword arguments.