code: def get_varlen_iter(self, start=0, std=5, min_len=5, max_deviation=3):
      max_len = self.bptt + max_deviation * std
      i = start
      while True:
          bptt = (
              self.bptt
              if np.random.random() < 0.95
              else self.bptt / 2.0
          )
          bptt = min(
              max_len, max(min_len, int(np.random.normal(bptt, std)))
          )
          data, target, seq_len = self.get_batch(i, bptt)
          i += seq_len
          yield data, target, seq_len
          if i >= self.data.size(0) - 2:
              break
  
imports: import os, sys
  import glob
  from collections import Counter, OrderedDict
  import numpy
  import torch
  from utils.vocabulary import Vocab
label_desc: Use image node_id 4 for calling the LMOrderedIterator obj's underlying member method code with example usage: obj.get_varlen_iter(start, std, min_len, max_deviation) without return types