code: func parseArgs(funcName string, args ...interface{}) (string, wire.BitcoinNet, error) {
  	if len(args) != 2 {
  		return "", 0, fmt.Errorf("invalid arguments to %s.%s -- "+
  			"expected database path and block network", dbType,
  			funcName)
  	}
  
  	dbPath, ok := args[0].(string)
  	if !ok {
  		return "", 0, fmt.Errorf("first argument to %s.%s is invalid -- "+
  			"expected database path string", dbType, funcName)
  	}
  
  	network, ok := args[1].(wire.BitcoinNet)
  	if !ok {
  		return "", 0, fmt.Errorf("second argument to %s.%s is invalid -- "+
  			"expected block network", dbType, funcName)
  	}
  
  	return dbPath, network, nil
  }
docs: // parseArgs parses the arguments from the database Open/Create methods.