new_contents: from ceph_deploy.hosts import common
  from ceph_deploy.lib.remoto import process
  
  
  def add(distro, args, monitor_keyring):
      hostname = distro.conn.remote_module.shortname()
      common.mon_add(distro, args, monitor_keyring, hostname)
      service = distro.conn.remote_module.which_service()
  
      process.run(
          distro.conn,
          [
              service,
              'ceph',
              '-c',
              '/etc/ceph/{cluster}.conf'.format(cluster=args.cluster),
              'start',
              'mon.{hostname}'.format(hostname=hostname)
          ],
          timeout=7,
      )
  
subject: create the add.py file for centos