class_docstr: Module for calculate the overall one-step-forward prediction accuracy.
  
  Example
  -------
  >>> probs = torch.tensor([[0.9, 0.1], [0.1, 0.9], [0.8, 0.2]]).unsqueeze(0)
  >>> stats = AccuracyStats()
  >>> stats.append(torch.log(probs), torch.tensor([1, 1, 0]).unsqueeze(0), torch.tensor([2/3]))
  >>> acc = stats.summarize()
  >>> print(acc)
  0.5
code: def __init__(self):
      self.correct = 0
      self.total = 0
  
imports: import torch
  from speechbrain.dataio.dataio import length_to_mask
label_desc: Use image node_id 1 to create a new AccuracyStats object  with example: obj = AccuracyStats()