import clr

clr.AddReference('RevitNodes')

import Revit

clr.ImportExtensions(Revit.GeometryConversion)



# Import DocumentManager and TransactionManager

clr.AddReference('RevitServices')

from RevitServices.Persistence import DocumentManager



# Import RevitAPI

clr.AddReference('RevitAPI')

from Autodesk.Revit.DB import *



doc = DocumentManager.Instance.CurrentDBDocument



assembly = UnwrapElement(IN[0])



OUT = assembly.BoundingBox[doc.ActiveView].ToProtoType()