class_docstr: PyTorchTranslateMultilingualTranslationTask is eventually subclasses
  fairseq.tasks.MultilingualTranslationTask. The major differences are-
  - There is no --data folder containing data binaries and vocabularies,
    instead we use paths from --vocabulary, --multilingual-*-text-file and
    --multilingual-*-binary-path
  - loss_weights is used to weigh losses from different datasets differently.
    This is achieved by using pytorch_translate's WeightedLanguagePairDataset
  - The dictionaries are instances of pytorch_translate's Dictionary class
class_docstr_tok: ["PyTorchTranslateMultilingualTranslationTask","is","eventually","subclasses","fairseq.tasks.MultilingualTranslationTask",".","The","major","differences","are-","-","There","is","no","--","data","folder","containing","data","binaries","and","vocabularies",",","instead","we","use","paths","from","--","vocabulary",",","--","multilingual-","*","-text-file","and","--","multilingual-","*","-binary-path","-","loss_weights","is","used","to","weigh","losses","from","different","datasets","differently",".","This","is","achieved","by","using","pytorch_translate","'s","WeightedLanguagePairDataset","-","The","dictionaries","are","instances","of","pytorch_translate","'s","Dictionary","class"]
code: def add_args(parser):
      PyTorchTranslateMultiTask.add_args(parser)
      """Add task-specific arguments to the parser."""
      parser.add_argument(
          "--vocabulary",
          type=str,
          metavar="EXPR",
          action="append",
          help=(
              "Per-language vocabulary configuration."
              "Path to vocabulary file must be in the format lang:path"
          ),
          default=[],
      )
      parser.add_argument(
          "--multilingual-train-text-file",
          type=str,
          metavar="EXPR",
          action="append",
          help=(
              "Path to train text file in the format "
              "src_lang-tgt_lang:source-path,target-path"
          ),
      )
      parser.add_argument(
          "--multilingual-eval-text-file",
          type=str,
          metavar="EXPR",
          action="append",
          help=(
              "Path to eval text file in the format "
              "src_lang-tgt_lang:source-path,target-path"
          ),
      )
      parser.add_argument(
          "--multilingual-train-binary-path",
          type=str,
          metavar="EXPR",
          action="append",
          help=(
              "Path to train binary file in the format "
              "src_lang-tgt_lang:source-path,target-path"
          ),
      )
      parser.add_argument(
          "--multilingual-eval-binary-path",
          type=str,
          metavar="EXPR",
          action="append",
          help=(
              "Path to eval binary file in the format "
              "src_lang-tgt_lang:source-path,target-path"
          ),
      )
  
file_path: translate/pytorch_translate/tasks/multilingual_task.py
imports: from collections import OrderedDict
  from fairseq import options
  from fairseq.data import RoundRobinZipDatasets
  from fairseq.tasks import register_task
  from pytorch_translate import constants
  from pytorch_translate.data import data, utils, weighted_data
  from pytorch_translate.tasks import utils
  from pytorch_translate.tasks.pytorch_translate_multi_task import PyTorchTranslateMultiTask
label_desc: Use image node_id 1 for calling the PyTorchTranslateMultilingualTranslationTask obj's underlying member method code with example usage: obj.add_args(parser) without return types