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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def Convert(self, values, start_index=0, end_index=None):
 """Converts given collection to exported values. This method uses a threadpool to do the conversion in parallel. It blocks for up to one hour until everything is converted. Args: values: Iterable object with values to convert. start_index: Start from this index in the collection. end_index: Finish processing on the (index - 1) element of the collection. If None, work till the end of the collection. Returns: Nothing. ConvertedBatch() should handle the results. """

    if not values:
      return

    try:
      total_batch_count = len(values) // self.batch_size
    except TypeError:
      total_batch_count = -1

    pool = ThreadPool.Factory(self.threadpool_prefix, self.threadpool_size)
    val_iterator = itertools.islice(values, start_index, end_index)

    pool.Start()
    try:
      for batch_index, batch in enumerate(
          collection.Batch(val_iterator, self.batch_size)):
        logging.debug("Processing batch %d out of %d", batch_index,
                      total_batch_count)

        pool.AddTask(
            target=self.ConvertBatch,
            args=(batch,),
            name="batch_%d" % batch_index,
            inline=False)

    finally:
      pool.Stop(join_timeout=3600)