code: def prepare_download():
      """
      Downloads and prepares various data files and resources. It
      downloads real-time DNS track data files (train set and dev
      noisy set).
      """
      # Real-time DNS track (train set + dev noisy set)
      for file_url in BLOB_NAMES:
          for split in SPLIT_LIST:
              if split in file_url:
                  split_name = split
  
          split_path = os.path.join(COMPRESSED_PATH, split_name)
          if not os.path.exists(split_path):
              os.makedirs(split_path)
          if not os.path.exists(DECOMPRESSED_PATH):
              os.makedirs(DECOMPRESSED_PATH)
  
          filename = file_url.split("/")[-1]
          download_path = os.path.join(split_path, filename)
          download_url = AZURE_URL + "/" + file_url
  
          if not validate_file(download_url, download_path):
              if os.path.exists(download_path):
                  resume_byte_pos = os.path.getsize(download_path)
              else:
                  resume_byte_pos = None
  
              download_file(
                  download_url,
                  download_path,
                  split_name,
                  filename,
                  resume_byte_pos=resume_byte_pos,
              )
          else:
              print(", \tDownload complete. Skipping")
          decompress_file(download_path, DECOMPRESSED_PATH, split_name)
  
      # Download RIR (impulse response) & BLIND testset
      rir_blind_test_download()
  
file_path: speechbrain/recipes/DNS/dns_download.py
imports: import os
  import ssl
  import shutil
  import zipfile
  import tarfile
  import certifi
  import argparse
  import fileinput
  import requests
  import urllib.request
  from tqdm.auto import tqdm
  from concurrent.futures import ThreadPoolExecutor
label_desc: Use image node_id 1 for calling a global function with example usage: prepare_download() without return types