code: def _import_extra_cpu_backends():
      try:
          from thinc_apple_ops import AppleOps
      except ImportError:
          pass
      try:
          from thinc_bigendian_ops import BigEndianOps
      except ImportError:
          pass
  
imports: import contextlib
  import threading
  from contextvars import ContextVar
  from typing import Any, Callable, Dict, Optional, Type, cast
  from ..None import registry
  from ..compat import cupy, has_cupy
  from ..util import assert_pytorch_installed, assert_tensorflow_installed, get_torch_default_device, is_cupy_array, require_cpu
  from ._cupy_allocators import cupy_pytorch_allocator, cupy_tensorflow_allocator
  from ._param_server import ParamServer
  from .cupy_ops import CupyOps
  from .mps_ops import MPSOps
  from .numpy_ops import NumpyOps
  from .ops import Ops
label_desc: Use image node_id 4 for calling a global function with example usage: _import_extra_cpu_backends() without return types