return new2old Region map from pwa_partition
return new2old Region map from pwa_partition

update docstring
rename var: parent -> parents
rename returned var: ppp -> new_ppp

tulip-control/tulip-control,necozay/tulip-control,necozay/tulip-control,tulip-control/tulip-control,necozay/tulip-control,tulip-control/tulip-control,necozay/tulip-control,necozay/tulip-control,tulip-control/tulip-control