code: def get_index_file_offsets(job_id, start_job_id):
      assert job_id >= start_job_id
      idx_start = SpecWriter.bytes_per_offset * (job_id - start_job_id)
      idx_end = (
          idx_start + 2 * SpecWriter.bytes_per_offset
      ) - 1  # `end` parameter in gcs is inclusive of last byte to return
      return (idx_start, idx_end)
  
imports: import logging
  from typing import Literal, Tuple
  from hailtop.utils import secret_alnum_string
label_desc: Use image node_id 1 for calling the SpecWriter obj's underlying member method code with example usage: obj.get_index_file_offsets(job_id, start_job_id) and returns: idx_start,  idx_end