type(obj) = <class 'sage.combinat.root_system.weyl_characters.WeightRing_with_category.element_class'>
version = 4.7.alpha2
obj =
'a1xa1(0,0,0,0) + 2*a1xa1(1,0,0,0) + a1xa1(2,2,3,0) + 3*a1xa1(0,1,0,0)'
