// existing file, such as a binary executable.
// It must be called before any data is written.
func (w *Writer) SetOffset(n int64) {
	if w.cw.count != 0 {
		panic("zip: SetOffset called after data was written")
	}
	w.cw.count = n
}

// Flush flushes any buffered data to the underlying writer.
// Calling Flush is not normally necessary; calling Close is sufficient.
func (w *Writer) Flush() error {

			cmd.Dir = w.context.Dir
		}
		cmd.Stderr = os.Stderr
		out, err := cmd.Output()
		if err != nil {
			log.Fatalf("loading imports: %v\n%s", err, out)
		}

		var stdPackages []string
		importMap := make(map[string]map[string]string)
		importDir := make(map[string]string)
		dec := json.NewDecoder(bytes.NewReader(out))
		for {
			var pkg struct {
				ImportPath, Dir string