code: def test_extra_str_normalization(self):
      raw_name = "S_P__A_M"
      normalized_name = "s-p-a-m"
      lhs = f"{raw_name!r} == extra"
      rhs = f"extra == {raw_name!r}"
  
      assert str(Marker(lhs)) == f'"{normalized_name}" == extra'
      assert str(Marker(rhs)) == f'extra == "{normalized_name}"'
  
imports: import collections
  import itertools
  import os
  import platform
  import sys
  from typing import cast
  import pytest
  from packaging._parser import Node
  from packaging.markers import InvalidMarker, Marker, UndefinedComparison, default_environment, format_full_version
label_desc: Use image node_id 13 for calling the TestMarker obj's underlying member method code with example usage: obj.test_extra_str_normalization() without return types