code: def from_config_file(config_file=None) -> "DeployConfig":
      config_file = first_extant_file(
          config_file,
          os.environ.get("HAIL_DEPLOY_CONFIG_FILE"),
          os.path.expanduser("~/.hail/deploy-config.json"),
          "/deploy-config/deploy-config.json",
      )
      if config_file is not None:
          log.info(f"deploy config file found at {config_file}")
          with open(config_file, "r", encoding="utf-8") as f:
              config = json.load(f)
          log.info(f'deploy config location: {config["location"]}')
      else:
          log.info(f"deploy config file not found: {config_file}")
          config = {
              "location": "external",
              "default_namespace": "default",
              "domain": get_user_config().get(
                  "global", "domain", fallback="hail.is"
              ),
          }
      return DeployConfig.from_config(config)
  
imports: from typing import Dict, Optional, TypeVar, Union
  import os
  import json
  import logging
  from ..utils import first_extant_file
  from .user_config import get_user_config
label_desc: Use image node_id 3 for calling the DeployConfig obj's underlying member method code with example usage: obj.from_config_file(config_file) and returns: DeployConfig