code: def download_seviri_hrit_20180228_1500(base_dir=None, subset=None):
      """Download the SEVIRI HRIT files for 2018-02-28T15:00.
  
      *subset* is a dictionary with the channels as keys and granules to download
      as values, eg::
  
        {"HRV": [1, 2, 3], "IR_108": [1, 2], "EPI": None}
  
      """
      files = generate_subset_of_filenames(subset)
  
      base_dir = base_dir or config.get("demo_data_dir", ".")
      subdir = os.path.join(base_dir, "seviri_hrit", "20180228_1500")
      os.makedirs(subdir, exist_ok=True)
      targets = []
      for the_file in files:
          target = os.path.join(subdir, the_file)
          targets.append(target)
          if os.path.isfile(target):
              continue
          download_url(ZENODO_BASE_URL + the_file, target)
      return targets
  
file_path: satpy/satpy/demo/seviri_hrit.py
imports: import logging
  import os.path
  from satpy import config
  from satpy.demo.utils import download_url
label_desc: Use image node_id 1 for calling a global function with example usage: download_seviri_hrit_20180228_1500(base_dir, subset) and returns: targets