Hi Edward,
The Transform node does support group positional identifiers (node.firstInGroup and node.lastInGroup). These are discussed in the Help documentation, see the following topic:
Data360 Analyze Server Help > Python scripting > API and script bindings
Specifically, the section on the node objects.
This information is also available online for the latest version of the product here:
https://help.precisely.com/r/Data360-Analyze/3.14/en-US/Data360-Analyze-Server-Help/Python-scripting/API-and-script-bindings
Here is a simple example of their use that concatenates the string values of the 'color' field in the Create Data node's default data set, grouped by the 'type' field.

Note that by default the Transform node will log a warning if the input data is not sorted by the group by field(s) [See the node's UnsortedInputBehavior property for details].
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Adrian Williams
Precisely Software Inc.
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