code: func (c *Config) Set(key, value string) error {
  	data, err := load(c.filename, c.passphrase)
  	if err != nil {
  		return errors.Wrapf(err, "failed to read secrects config %s: %s", c.filename, err)
  	}
  
  	old := data[key]
  	if value == old {
  		return nil
  	}
  
  	data[key] = value
  	return save(c.filename, c.passphrase, data)
  }
docs: // Set writes the requested key to disk