def get_lv_vg(ns, lv):
    lv = common.str2device(ns, lv)
    return lv.first_associator(AssocClass="LMI_LVAllocatedFromStoragePool")
Returns field's value just before saving.
dataset/ETHPy150Open openlmi/openlmi-scripts/commands/storage/lmi/scripts/storage/lvm.py/get_lv_vg--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/django/db/models/fields/files.py/FileField.pre_save