Maybe with a group of people huddled together in a blanket fort? I’ve never experienced temperatures like that myself but I remember a whole lot of advice going around during last year (?) power blackouts over winter in the US. People camping in their living room and staying in the one room to concentrate heat sources. That said, I don’t think it went down to -20 C though. Wouldn’t water pipes freeze and stuff as well? I suspect maybe it won’t be survivable. 🤔