code: def _normalize_extra_values(results: Any) -> Any:
      """
      Normalize extra values.
      """
      if isinstance(results[0], tuple):
          lhs, op, rhs = results[0]
          if isinstance(lhs, Variable) and lhs.value == "extra":
              normalized_extra = canonicalize_name(rhs.value)
              rhs = Value(normalized_extra)
          elif isinstance(rhs, Variable) and rhs.value == "extra":
              normalized_extra = canonicalize_name(lhs.value)
              lhs = Value(normalized_extra)
          results[0] = lhs, op, rhs
      return results
  
imports: import operator
  import os
  import platform
  import sys
  from typing import Any, Callable, Dict, List, Optional, Tuple, Union
  from ._parser import MarkerAtom, MarkerList, Op, Value, Variable, parse_marker
  from ._tokenizer import ParserSyntaxError
  from .specifiers import InvalidSpecifier, Specifier
  from .utils import canonicalize_name
label_desc: Use image node_id 1 for calling a global function with example usage: _normalize_extra_values(results) and returns: results