code: def download_single_shard(
      shard_url: str, dst_filename: str, chunk_size_mb: int = 512
  ) -> None:
      print(
          f"Downloading single shard from {shard_url} to {dst_filename}"
      )
      with requests.get(shard_url, stream=True) as request:
          assert request.ok, "Downloading shard failed"
          with open(dst_filename, "wb") as dst:
              for chunk in request.iter_content(
                  chunk_size=chunk_size_mb * 1 << 20
              ):
                  bytes_written = dst.write(chunk)
                  print(
                      f"Wrote {bytes_written / (1 << 20):0.02f} MB to {dst_filename}"
                  )
  
imports: from typing import Union, Iterable, Tuple, Optional
  import os
  import requests
  import shutil
  import sys
  import tensorflow.compat.v1
  import time
  from ray.util.scheduling_strategies import NodeAffinitySchedulingStrategy
  import ray
label_desc: Use image node_id 4 for calling a global function with example usage: download_single_shard(shard_url, dst_filename, chunk_size_mb) without return types