code: def get_parallel_regions_block(batch):
      
      samples = [utils.to_single_data(d) for d in batch]
      regions = _get_parallel_regions(samples[0])
      out = []
      # Currently don't have core information here so aim for about 10 items per partition
      n = 10
      for region_block in tz.partition_all(n, regions):
          out.append({"region_block": ["%s:%s-%s" % (c, s, e) for c, s, e in region_block]})
      return out
docs: CWL target to retrieve block group of callable regions for parallelization.
  
      Uses blocking to handle multicore runs.