code: def ssh_ping(
      host,
      user=None,
      private_key=None,
      verbose=False,
      connect_timeout=DEFAULT_CONNECT_TIMEOUT,
      port=None,
      proxy=None,
  ):
      host = _full_host(host, user)
      opts = _ssh_opts(
          private_key, verbose, connect_timeout, port, proxy
      )
      cmd = ["ssh"] + opts + [host, "true"]
      log.debug("ssh cmd: %r", cmd)
      result = subprocess.call(cmd)
      if result != 0:
          raise remotelib.Down(f"cannot reach host {host}")
  
file_path: guildai/guild/remotes/ssh_util.py
imports: import logging
  import subprocess
  from guild import remote
label_desc: Use image node_id 1 for calling a global function with example usage: ssh_ping(host, user, private_key, verbose, connect_timeout, port, proxy) without return types