code: def _flag_function_or_expanded_sequence(s):
      """Returns a flag function spec or expanded function if applicable.
  
      If s can be decoded as a flag function it is returned as a string
      value to prevent it from being decoded by YAML, which can
      accidentally decode it as a list (see below for details).
  
      If s can be expanded to a sequence, the return value is a list
      containing the expanded items.
  
      Guild treats "[1:2]" as an anonymous flag function, which is
      passed along as a string to be decoded downstream. However, YAML
      treats "[1:2]" as a list containing a time value (one minute, two
      seconds), and therefore returns the value `[62]`. This function
      ensures that anonymous flag functions are returned as decoded
      string values. Provided this function is used prior to YAML
      decoding, the value is decoded correctly.
  
      Raises ValueError if s is not a special flag function.
  
      Raises TypeError if the arguments provided to flag function are
      invalid.
      """
      name, args = decode_flag_function(s)
      if _is_anonymous_flag_function(name, args):
          return s
      if _is_sequence_flag_function(name):
          return _expand_sequence(name, args)
      raise ValueError(s)
  
imports: import logging
  import os
  import re
  import yaml
  from guild import util
  from guild import yaml_util
label_desc: Use image node_id 13 for calling a global function with example usage: _flag_function_or_expanded_sequence(s) and returns: s, _expand_sequence