code: def clear_cache(dataset_name=None):
      
      dr = data_resources[dataset_name]
      if 'dirs' in dr:
          for dirs, files in zip(dr['dirs'], dr['files']):
              for dir, file in zip(dirs, files):
                  path = os.path.join(data_path, dataset_name, dir, file)
                  if os.path.exists(path):
                      logging.info("clear_cache: removing " + path)
                      os.unlink(path)
              for dir in dirs:
                  path = os.path.join(data_path, dataset_name, dir)
                  if os.path.exists(path):
                      logging.info("clear_cache: remove directory " + path)
                      os.rmdir(path)
          
      else:
          for file_list in dr['files']:
              for file in file_list:
                  path = os.path.join(data_path, dataset_name, file)
                  if os.path.exists(path):
                      logging.info("clear_cache: remove " + path)
                      os.unlink(path)
docs: Remove a data set from the cache