code: func (c *Client) SnapshotDatabaseServer(identifier string) (*DatabaseSnapshot, error) {
  	dbs := new(DatabaseServer)
  	res, err := c.MakeApiRequest("POST", "/1.0/database_servers/"+identifier+"/snapshot", nil, &dbs)
  	if err != nil {
  		return nil, err
  	}
  	snapID := getLinkRel(res.Header.Get("Link"), "dbi", "snapshot")
  	if snapID != nil {
  		snap := new(DatabaseSnapshot)
  		snap.Id = *snapID
  		return snap, nil
  	}
  	return nil, nil
  }
docs: // SnapshotDatabaseServer requests a snapshot of an existing database server.