code: def cast_unicode(s, encoding="utf8", errors="strict"):
      """cast bytes or unicode to unicode"""
      if isinstance(s, bytes):
          return s.decode(encoding, errors)
      elif isinstance(s, unicode):
          return s
      else:
          raise TypeError("Expected unicode or bytes, got %r" % s)
  
label_desc: Use image node_id 2 for calling a global function with example usage: cast_unicode(s, encoding, errors) and returns: s, s