code: def __len__(self):
      return len(self.tokens) - self.num_non_words
  
imports: from copy import deepcopy
  import torch
  import torch.nn
  from graph4nlp.pytorch.modules.prediction.generation.base import DecoderBase
label_desc: Use image node_id 3 for calling the Hypothesis obj's underlying member method code with example usage: obj.__len__() and returns: unknown