How to select ILvl0Descendants when exporting via calculation manager?

Summary:

How to select ILvl0Descendants when exporting via calc manager?

Content (required):

When exporting data via a job, you can specify members sets using the "ILvl0Descendants" function.

However, when exporting data via a rule (or calc manager), there is no "ILvl0Descendants" function.

Out of the available functions in calc mgr (@IDESCENDANTS, @RELATIVE, @IRDESCENDANTS, etc)., what would be the closest to "ILv10Descendants"?

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