code: def step_impl_user_checks_availability(context):
      """Check availability."""
      from datetime import datetime
  
      from satpy import Scene, find_files_and_readers
  
      os.chdir("/tmp/")
      reader_files = find_files_and_readers(
          sensor="viirs",
          start_time=datetime(2015, 3, 11, 11, 20),
          end_time=datetime(2015, 3, 11, 11, 26),
      )
      scn = Scene(filenames=reader_files)
      context.available_dataset_ids = scn.available_dataset_ids()
  
file_path: satpy/satpy/tests/features/steps/steps-load.py
imports: import os
  from urllib.request import urlopen
  from behave import given, then, use_step_matcher, when
label_desc: Use image node_id 5 for calling a global function with example usage: step_impl_user_checks_availability(context) without return types