code: def register_backend(
      backend: str,
      *,
      buildkit_support: bool,
      health: t.Callable[[], bool],
      construct_build_args: t.Callable[P, Arguments],
      binary: str | None = None,
      build_cmd: t.Sequence[str] | None = None,
      env: dict[str, str] | None = None,
  ):
      """
      Register a custom backend, provided with a build and health check implementation.
  
      Args:
          backend: Name of the backend.
          buildkit_support: Whether the backend has support for BuildKit.
          health: Health check implementation. This is a callable that takes no
                  argument and returns a boolean.
          construct_build_args: This is a callable that takes possible backend keyword arguments
                                and returns a list of command line arguments.
          env: Default environment variables dict for this OCI builder implementation.
          binary: Optional binary path. If not provided, the binary will use the backend name.
                  Make sure that the binary is on your ``PATH``.
          build_cmd: Optional build command. If not provided, the command will be 'build'.
  
      Examples:
  
      .. code-block:: python
  
          from bentoml.container import register_backend
  
          register_backend(
              "lima",
              binary=shutil.which("limactl"),
              buildkit_support=True,
              health=buildx_health,
              construct_build_args=buildx_build_args,
              env={"DOCKER_BUILDKIT": "1"},
          )
      """
      if backend in BUILDER_REGISTRY:
          raise ValueError(f"Backend {backend} already registered.")
      if binary is None:
          binary = backend
      try:
          BUILDER_REGISTRY[backend] = OCIBuilder.create(
              binary,
              env=env,
              build_cmd=build_cmd,
              enable_buildkit=buildkit_support,
              construct_build_args=construct_build_args,
              health=health,
          )
      except Exception as e:  # pylint: disable=broad-except
          logger.error(
              "Failed to register backend %s: %s",
              backend,
              e,
              exc_info=sys.exc_info(),
          )
          raise e from None
  
imports: from __future__ import annotations
  import contextlib
  import importlib
  import logging
  import os
  import sys
  import types
  import typing
  from typing import TYPE_CHECKING
  import fs
  import fs.mirror
  from simple_di import Provide
  from simple_di import inject
  from ...exceptions import InvalidArgument
  from ..configuration.containers import BentoMLContainer
  from ..utils import bentoml_cattr
  from .base import OCIBuilder
  from .generate import generate_containerfile
label_desc: Use image node_id 6 for calling a global function with example usage: register_backend(backend) without return types