code: def download(id_or_alias):
      db = read_checkpoint_db()
      checkpoint = get_checkpoint(db, id_or_alias)
      if not checkpoint:
          click.echo(
              "Checkpoint '{}' not found in index.".format(id_or_alias)
          )
          return
  
      if checkpoint["source"] != "remote":
          click.echo(
              "Checkpoint is not remote. If you intended to download a remote "
              "checkpoint and used an alias, try using the id directly."
          )
          return
  
      if checkpoint["status"] != "NOT_DOWNLOADED":
          click.echo("Checkpoint is already downloaded.")
          return
  
      download_remote_checkpoint(db, checkpoint)
  
imports: import click
  import json
  import os
  import shutil
  import six
  import requests
  import tarfile
  import tempfile
  import tensorflow
  import uuid
  from datetime import datetime
  from luminoth import __version__
  from luminoth.utils.config import get_config
  from luminoth.utils.homedir import get_luminoth_home
label_desc: Use image node_id 23 for calling a global function with example usage: download(id_or_alias) without return types