def transpose_list_of_lists(lol):
  """Transpose a list of equally-sized python lists.

  Args:
    lol: a list of lists
  Returns:
    a list of lists
  """
  assert lol, "cannot pass the empty list"
  return [list(x) for x in zip(*lol)]
Transpose a list of equally-sized python lists.

  Args:
    lol: a list of lists
  Returns:
    a list of lists
  
tensor2tensor/utils/expert_utils.py