code: def create_notebook_checkpoint(
      backend: NeptuneBackend,
  ) -> Tuple[Optional[str], Optional[str]]:
      notebook_id = os.getenv(NEPTUNE_NOTEBOOK_ID, None)
      notebook_path = os.getenv(NEPTUNE_NOTEBOOK_PATH, None)
  
      checkpoint_id = None
      if notebook_id is not None and notebook_path is not None:
          checkpoint_id = create_checkpoint(
              backend=backend,
              notebook_id=notebook_id,
              notebook_path=notebook_path,
          )
  
      return notebook_id, checkpoint_id
  
imports: import os
  import threading
  from platform import node
  from typing import TYPE_CHECKING, List, Optional, Tuple, Union
  from typing_extensions import Literal
  from neptune.attributes.constants import SYSTEM_DESCRIPTION_ATTRIBUTE_PATH, SYSTEM_FAILED_ATTRIBUTE_PATH, SYSTEM_HOSTNAME_ATTRIBUTE_PATH, SYSTEM_NAME_ATTRIBUTE_PATH, SYSTEM_TAGS_ATTRIBUTE_PATH
  from neptune.common.warnings import NeptuneWarning, warn_once
  from neptune.envs import CONNECTION_MODE, CUSTOM_RUN_ID_ENV_NAME, MONITORING_NAMESPACE, NEPTUNE_NOTEBOOK_ID, NEPTUNE_NOTEBOOK_PATH
  from neptune.exceptions import InactiveRunException, NeedExistingRunForReadOnlyMode, NeptunePossibleLegacyUsageException, NeptuneRunResumeAndCustomIdCollision
  from neptune.internal.backends.api_model import ApiExperiment
  from neptune.internal.backends.neptune_backend import NeptuneBackend
  from neptune.internal.container_type import ContainerType
  from neptune.internal.hardware.hardware_metric_reporting_job import HardwareMetricReportingJob
  from neptune.internal.id_formats import QualifiedName
  from neptune.internal.init.parameters import ASYNC_LAG_THRESHOLD, ASYNC_NO_PROGRESS_THRESHOLD, DEFAULT_FLUSH_PERIOD, DEFAULT_NAME, OFFLINE_PROJECT_QUALIFIED_NAME
  from neptune.internal.notebooks.notebooks import create_checkpoint
  from neptune.internal.state import ContainerState
  from neptune.internal.streams.std_capture_background_job import StderrCaptureBackgroundJob, StdoutCaptureBackgroundJob
  from neptune.internal.utils import verify_collection_type, verify_type
  from neptune.internal.utils.dependency_tracking import FileDependenciesStrategy, InferDependenciesStrategy
  from neptune.internal.utils.git import to_git_info, track_uncommitted_changes
  from neptune.internal.utils.hashing import generate_hash
  from neptune.internal.utils.limits import custom_run_id_exceeds_length
  from neptune.internal.utils.ping_background_job import PingBackgroundJob
  from neptune.internal.utils.runningmode import in_interactive, in_notebook
  from neptune.internal.utils.source_code import upload_source_code
  from neptune.internal.utils.traceback_job import TracebackJob
  from neptune.internal.websockets.websocket_signals_background_job import WebsocketSignalsBackgroundJob
  from neptune.metadata_containers import MetadataContainer
  from neptune.metadata_containers.abstract import NeptuneObjectCallback
  from neptune.types import GitRef, StringSeries
  from neptune.types.atoms.git_ref import GitRefDisabled
  from neptune.types.mode import Mode
label_desc: Use image node_id 4 for calling a global function with example usage: create_notebook_checkpoint(backend) and returns: notebook_id,  checkpoint_id