docstr: Return None to allow model to dictate max sentence length allowed
code: def max_positions(self):
      """Return None to allow model to dictate max sentence length allowed"""
      return None
  
file_path: translate/pytorch_translate/tasks/pytorch_translate_multi_task.py
imports: from fairseq import models
  from fairseq.data import data_utils, FairseqDataset
  from fairseq.models import FairseqMultiModel
  from fairseq.tasks.multilingual_translation import MultilingualTranslationTask
  from pytorch_translate.data import iterators
label_desc: Use image node_id 3 for calling the PyTorchTranslateMultiTask obj's underlying member method code with example usage: obj.max_positions() and returns: None