class_docstr: Dataset scheduling for multiple text-to-text problems.
class_docstr_tok: ["Dataset","scheduling","for","multiple","text-to-text","problems","."]
docstr: Set this to a positive integer if some of the problems are packed.
docstr_tok: ["Set","this","to","a","positive","integer","if","some","of","the","problems","are","packed","."]
code: def packed_length(self):
      """Set this to a positive integer if some of the problems are packed."""
      return None
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import functools
  import os
  import numpy
  from tensor2tensor.data_generators import problem
  from tensor2tensor.data_generators import text_problems
  import tensorflow.compat.v1
label_desc: Use image node_id 3 for calling the MultiText2TextProblem obj's underlying member method code with example usage: obj.packed_length() and returns: None