Why does this here work in one case, but not in the other?

parameters={
                                                   "bastionHostName": "%s-bastion" % (location),
                                                   "publicIpAddressName": self.pip.name,
                                                   "location": location,
                                                   "bastionServicesVnetName": vnet_name,
                                                   "bastionServicesSubnetName": self.subnet.name
                                               }