code: def is_known_platform(platform: str) -> bool:
      # A platform is valid if there is a registered factory for it. It does not
      # matter if we were unable to initialize that platform; we only care that
      # we've heard of it and it isn't, e.g., a typo.
      return (
          platform in _backend_factories.keys()
          or platform in _platform_aliases.keys()
      )
  
imports: from __future__ import annotations
  from __future__ import annotations
  from collections.abc import Mapping
  import dataclasses
  from functools import lru_cache, partial
  import importlib
  import json
  import logging
  import os
  import pkgutil
  import platform
  import sys
  import threading
  from typing import Any, Callable, Union
  import warnings
  from jax._src import config
  from jax._src import distributed
  from jax._src import traceback_util
  from jax._src import util
  from jax._src import hardware_utils
  from jax._src.cloud_tpu_init import maybe_import_libtpu
  from jax._src.lib import cuda_versions
  from jax._src.lib import xla_client
  from jax._src.lib import xla_extension
  from jax._src.lib import xla_extension_version
label_desc: Use image node_id 13 for calling a global function with example usage: is_known_platform(platform) and returns: unknown