code: def draw_nodes(self):
          
          node_r = self.node_sizes
          for i, node in enumerate(self.nodes):
              x = self.node_coords["x"][i]
              y = self.node_coords["y"][i]
              color = self.node_colors[i]
              node_patch = patches.Ellipse(
                  (x, y), node_r[i], node_r[i], lw=0, color=color, zorder=2
              )
              self.ax.add_patch(node_patch)
docs: Draw nodes to screen.