code: def op(self) -> OpName | None:
      if tkn := self.expect(lx.IDENTIFIER):
          return OpName(tkn.text)
      return None
  
imports: from dataclasses import dataclass, field
  from typing import NamedTuple, Callable, TypeVar, Literal, cast
  import lexer
  from plexer import PLexer
label_desc: Use image node_id 12 for calling the Parser obj's underlying member method code with example usage: obj.op() and returns: None, OpName