code: def get_uris(config):
      
      file_names = []
      if config.INPUT_DATA is None:
          sys.stderr.write("you need to provide INPUT_DATA in config\n")
          sys.exit(1)
      if isinstance(config.INPUT_DATA, basestring):
          config.INPUT_DATA = [config.INPUT_DATA]
      file_size = 0
      for uri in config.INPUT_DATA:
          for regex, uri_method, _, _ in URI_REGEXES:
              m = regex.match(uri)
              if m is not None:
                  file_size += uri_method(m, file_names, config)
                  break
      print("going to process {} files...".format(len(file_names)))
      return file_size, file_names
docs: returns a tuple of total file size in bytes, and the list of files