code: func FindProcess(pid int) (process *os.Process, err error) {
  	process, err = findProcess(pid)
  	if err != nil {
  		_ = process.Release()
  		process = nil
  	}
  	return process, err
  }
docs: // FindProcess wraps os.Findprocess [1] to return a public ErrNotFound
  // if the process does not exist.  The returned process will be nil if
  // and only if the returned err is non-nil.
  //
  // [1]: https://golang.org/pkg/os/#FindProcess