code: def resolve_filenames(all_expr):
          
          files = []
          for expr in all_expr.split(','):
              expr = expr.strip()
              files += fs.get_fs(expr).resolve_filenames(expr)
          log.debug('Filenames: {0}'.format(files))
          return files
docs: resolve expression for a filename
  
          :param all_expr:
              A comma separated list of expressions. The expressions can contain
              the wildcard characters ``*`` and ``?``. It also resolves Spark
              datasets to the paths of the individual partitions
              (i.e. ``my_data`` gets resolved to
              ``[my_data/part-00000, my_data/part-00001]``).
  
          :returns: A list of file names.
          :rtype: list