code: def postprocessing(circuit):
      fig, ax = draw_mpl(circuit)(1.2345, 1.2345)
      fig.suptitle("My Circuit", fontsize="xx-large")
  
      options = {
          "facecolor": "white",
          "edgecolor": "#f57e7e",
          "linewidth": 6,
          "zorder": -1,
      }
      box1 = plt.Rectangle(
          (-0.5, -0.5), width=3.0, height=4.0, **options
      )
      ax.add_patch(box1)
  
      ax.annotate(
          "CSWAP",
          xy=(3, 2.5),
          xycoords="data",
          xytext=(3.8, 1.5),
          textcoords="data",
          arrowprops={"facecolor": "black"},
          fontsize=14,
      )
  
      plt.savefig(folder / "postprocessing.png")
      plt.close()
  
file_path: pennylane/doc/_static/draw_mpl/draw_mpl_examples.py
imports: import pathlib
  import matplotlib.pyplot
  import pennylane
  from pennylane import draw_mpl
label_desc: Use image node_id 5 for calling a global function with example usage: postprocessing(circuit) without return types