code: def _parse_extras_list(tokenizer: Tokenizer) -> List[str]:
      """
      extras_list = identifier (wsp* ',' wsp* identifier)*
      """
      extras: List[str] = []
  
      if not tokenizer.check("IDENTIFIER"):
          return extras
  
      extras.append(tokenizer.read().text)
  
      while True:
          tokenizer.consume("WS")
          if tokenizer.check("IDENTIFIER", peek=True):
              tokenizer.raise_syntax_error(
                  "Expected comma between extra names"
              )
          elif not tokenizer.check("COMMA"):
              break
  
          tokenizer.read()
          tokenizer.consume("WS")
  
          extra_token = tokenizer.expect(
              "IDENTIFIER", expected="extra name after comma"
          )
          extras.append(extra_token.text)
  
      return extras
  
imports: import ast
  from typing import Any, List, NamedTuple, Optional, Tuple, Union
  from ._tokenizer import DEFAULT_RULES, Tokenizer
label_desc: Use image node_id 6 for calling a global function with example usage: _parse_extras_list(tokenizer) and returns: extras, extras