code: def positions_for(tokens, past_length):
      batch_size = tf.shape(input=tokens)[0]
      nsteps = tf.shape(input=tokens)[1]
      return expand_tile(past_length + tf.range(nsteps), batch_size)
  
file_path: finetune/finetune/base_models/gpt2/featurizer.py
imports: import functools
  import tensorflow
  from finetune.util.shapes import shape_list, lengths_from_eos_idx
  from finetune.optimizers.recompute_grads import recompute_grad
  from finetune.nn.activations import gelu
  from finetune.base_models.gpt.featurizer import norm, dropout, get_pos_values
label_desc: Use image node_id 11 for calling a global function with example usage: positions_for(tokens, past_length) and returns: expand_tile