Thank you nature! A few times today I've opened the window and the wasp has let itself out (I also like wasps and don't feel danger by them or feel need to wave my hands). I've also tested their temperament and they are not aggressive.
I also seem to have a knack of opening the door or window at the right time and they let themselves out. They are actually very calm flying object...

When you are calm, they are calm...
If you are scared or over-active it doesn't help their interpretation.

You can test this by them letting them investigate and it's a great test of trust. Much like humans (without putting them in the same category) but it's a great way to say "it's not gong to kill me so let's see if what other people say about is correct and just hold my nerve... and just love nature. Stings and all ! Because it's all full of wonder / wonderment and diversity rescues humanity.