Remove collections.Counter, because python 2.6 does not have "Counter"
Remove collections.Counter, because python 2.6 does not have "Counter"

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