I am writing a macro to generate tool holders in Gibbscam and I am stuck at importing the solids. Is there any function that I can call to import a parasolid into an open part?

The tool holder comes in two parts: Form (CAT40, BT45 etc) and Holder (Weldon, collet etc). I want to perform a union on the two solids immediatley after import and define the single solid as toolHolderSolid.

EX:

!Union solids and define holder solid
formSolid = SolidRef
holderSolid = SolidRef

SOLID_UNION formSolid, holderSolid

toolHolderSolid = SolidRef

Problem is I don't know what the SolidRef variable would be for either of the solids. Keeping in mind that the macro could be run at any time the name of the solid could be anything that fits "Import<n>". Anyone done this before?