In Openlane PDN flow, Is it possible to create only core ring without power grid for some power ? Background: In MPW shuttle XOR check to pass we need to have 4 POWER + 4 GROUND core ring in user project, even though logic uses only one set of POWER/GROUND. I am tried to masking the add_pdn_strip section in pdn_cfg file, but end up with below error

key "straps" not known in dictionary