code: def plot():
      fig, ax = plt.subplots()
      img = ax.imshow(trellis.T, origin="lower")
      ax.annotate("- Inf", (trellis.size(1) / 5, trellis.size(1) / 1.5))
      ax.annotate(
          "+ Inf",
          (trellis.size(0) - trellis.size(1) / 5, trellis.size(1) / 3),
      )
      fig.colorbar(img, ax=ax, shrink=0.6, location="bottom")
      fig.tight_layout()
  
file_path: audio/examples/tutorials/forced_alignment_tutorial.py
imports: import torch
  import torchaudio
  from dataclasses import dataclass
  import IPython
  import matplotlib.pyplot
label_desc: Use image node_id 3 for calling a global function with example usage: plot() without return types