code: def _validate(self) -> None:
      if not self._supported_platform:
          raise OSError("Valgrind is not supported on this platform.")
  
      missing_cmds = [
          cmd
          for cmd, available in self._commands_available.items()
          if not available
      ]
      if missing_cmds:
          raise OSError("Missing: " + ", ".join(missing_cmds))
  
imports: import collections
  import enum
  import dataclasses
  import itertools
  import os
  import pickle
  import re
  import shutil
  import subprocess
  import sys
  import textwrap
  from typing import cast, Any, Callable, DefaultDict, Dict, Iterator, List, NamedTuple, Optional, Tuple, Union, TYPE_CHECKING
  import torch
  from torch.utils.benchmark.utils import common, cpp_jit
  from torch.utils.benchmark.utils._stubs import CallgrindModuleType
  import operator
label_desc: Use image node_id 2 for calling the _ValgrindWrapper obj's underlying member method code with example usage: obj._validate() without return types