code: def subscribe(ctx, dataset):
      """Subscribe to an existing dataset."""
      marketplace = Marketplace()
      marketplace.subscribe(dataset)
  
imports: import errno
  import os
  from functools import wraps
  import re
  import click
  import sys
  import logbook
  import pandas
  from catalyst.marketplace.marketplace import Marketplace
  from six import text_type
  from catalyst.data import bundles
  from catalyst.exchange.exchange_bundle import ExchangeBundle
  from catalyst.exchange.utils.exchange_utils import delete_algo_folder
  from catalyst.utils.cli import Date, Timestamp
  from catalyst.utils.run_algo import _run, load_extensions
  from catalyst.exchange.utils.bundle_utils import EXCHANGE_NAMES
  from catalyst.utils.remote import remote_backtest, get_remote_status
label_desc: Use image node_id 17 for calling a global function with example usage: subscribe(ctx, dataset) without return types