handle duplicated indices in lib.direct_sum
handle duplicated indices in lib.direct_sum

sunqm/pyscf,sunqm/pyscf,gkc1000/pyscf,gkc1000/pyscf,sunqm/pyscf,sunqm/pyscf,gkc1000/pyscf,gkc1000/pyscf,gkc1000/pyscf