code: func (c *Client) GetReceivedByAddressAsync(address btcutil.Address) FutureGetReceivedByAddressResult {
  	addr := address.EncodeAddress()
  	cmd := btcjson.NewGetReceivedByAddressCmd(addr, nil)
  	return c.sendCmd(cmd)
  
  }
docs: // GetReceivedByAddressAsync returns an instance of a type that can be used to
  // get the result of the RPC at some future time by invoking the Receive
  // function on the returned instance.
  //
  // See GetReceivedByAddress for the blocking version and more details.