def preload_all_tenants(self):

        tenants, more = keystone.tenant_list(self._request)
        # Cache all tenants on right indexes, this is more effective than to
        # obtain large number of tenants one by one by keystone.tenant_get
        for t in tenants:
            self._tenants[t.id] = t
Preloads all teannts into dictionary.
dataset/ETHPy150Open Havate/havate-openstack/proto-build/gui/horizon/Horizon_GUI/openstack_dashboard/api/ceilometer.py/CeilometerUsage.preload_all_tenants