Update field of a Tiddler whose name derived from macro

[MagoArcade]

Hi. The below:

\define NodePath()
$:/plugins/felixhayashi/tiddlymap/graph/views/$(DDView)$/filter/nodes
\end

returns:

$:/plugins/felixhayashi/tiddlymap/graph/views/TestView/filter/nodes

I want to change the value of a field "filter" of the Tiddler of the name generated by the macro. Basically, I want to get the existing field value, append some text to the end of this and then save the updated value. E.g. Existing filter field = "Hello" ; I want to append " World" to change the field to "Hello World"

What is the best way to achieve this?

Thanks