code: func getChecker(cCmd *cobra.Command) *ssh.HostKeyChecker {
  	strictHostKeyChecking, _ := cmdFleet.PersistentFlags().GetBool("strict-host-key-checking")
  	if !strictHostKeyChecking {
  		return nil
  	}
  
  	knownHostsFile, _ := cmdFleet.PersistentFlags().GetString("known-hosts-file")
  	keyFile := ssh.NewHostKeyFile(knownHostsFile)
  	return ssh.NewHostKeyChecker(keyFile)
  }
docs: // getChecker creates and returns a HostKeyChecker, or nil if any error is encountered