code: def __iter__(self):
      queue = mp.Queue(self.queue_size)
  
      Process = partial(mp.Process, target=map_to_queue, daemon=True)
  
      it = ParApplyIterator(
          procs=[
              Process(
                  args=(
                      self.fn,
                      emitter,
                      queue,
                      self.encode,
                      self.batch_size,
                  )
              )
              for emitter in self.emitter
          ],
          queue=queue,
          decode=self.decode,
      )
      it.start()
      return it
  
file_path: gluonts/src/gluonts/nursery/glide/parallel.py
imports: import multiprocessing
  from functools import partial
  from toolz.itertoolz import partition_all
  from toolz.functoolz import identity
label_desc: Use image node_id 2 for calling the ParApply obj's underlying member method code with example usage: obj.__iter__() and returns: it