bb_parse.py

import FreeCADGui as Gui

a = Gui.Selection.getSelection()

for i in a:
    xl = i.Shape.BoundBox.XLength/25.4
    yl = i.Shape.BoundBox.YLength/25.4
    zl = i.Shape.BoundBox.ZLength/25.4
    print i.Label +", x="+ str(xl)+" , y="+str(yl)+" , z="+str(zl)