cache.go
func (c *cache) SaveFile(fname string) error {
	fp, err := os.Create(fname)
	if err != nil {
		return err
	}
	err = c.Save(fp)
	if err != nil {
		fp.Close()
		return err
	}
	return fp.Close()
}
func (c *cache) SaveFile(fname string) error {
	fp, err := os.Create(fname)
	if err != nil {
		return err
	}
	err = c.Save(fp)
	if err != nil {
		fp.Close()
		return err
	}
	return fp.Close()
}
// Save the cache's items to the given filename, creating the file if it
// doesn't exist, and overwriting it if it does.
//
// NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the
// documentation for NewFrom().)