code: def get_all_user_ssh_settings(application_name):
      
      settings = get_ssh_settings(application_name)
      settings.update(get_ssh_settings(application_name, user='nova'))
      return settings
docs: Retrieve the known host entries and public keys for application
  
      Retrieve the known host entries and public keys for application for all
      units of the given application related to this application for root user
      and nova user.
  
      :param application_name: Name of application eg nova-compute-something
      :type application_name: str
      :returns: Public keys + host keys for all units for app + user combination.
      :rtype: dict