code: def add_subparser(parser):
      """Add the subparser that needs to be used for this command"""
      serve_parser = parser.add_parser(
          "serve", help=DESCRIPTION, description=DESCRIPTION
      )
  
      serve_parser.add_argument(
          "-c",
          "--config",
          type=argparse.FileType("r"),
          metavar="path-to-config",
          help="user provided " "orion configuration file",
      )
  
      serve_parser.set_defaults(func=main)
  
      return serve_parser
  
file_path: orion/src/orion/core/cli/serve.py
imports: import argparse
  import logging
  from gunicorn.app.base import BaseApplication
  from orion.core.io import experiment_builder
  from orion.serving.webapi import WebApi
  from orion.storage.base import setup_storage
label_desc: Use image node_id 1 for calling a global function with example usage: add_subparser(parser) and returns: serve_parser