nodes: 0, module; 1, function_definition; 2, function_name:sort_prefixes; 3, parameters; 4, block; 5, identifier:orig; 6, default_parameter; 7, expression_statement; 8, expression_statement; 9, for_statement; 10, return_statement; 11, identifier:prefixes; 12, string; 13, comment:"""Returns a sorted list of prefixes.
  
      Args:
          orig (str): Unsorted list of prefixes.
          prefixes (str): List of prefixes, from highest-priv to lowest.
      """; 14, assignment; 15, identifier:prefix; 16, identifier:prefixes; 17, block; 18, identifier:new; 19, string_content:@+; 20, identifier:new; 21, string; 22, if_statement; 23, comparison_operator:prefix in orig; 24, block; 25, identifier:prefix; 26, identifier:orig; 27, expression_statement; 28, augmented_assignment; 29, identifier:new; 30, identifier:prefix
code: def sort_prefixes(orig, prefixes='@+'):
      """Returns a sorted list of prefixes.
  
      Args:
          orig (str): Unsorted list of prefixes.
          prefixes (str): List of prefixes, from highest-priv to lowest.
      """
      new = ''
      for prefix in prefixes:
          if prefix in orig:
              new += prefix
      return new