I have never had to do it, so I cannot imagine it being easy.
But I am watching this thread with interest to see if there is something we are missing about how to get it open without doing damage to other bits.
If it unlocks then there may be an old skool, car thief way of actuating the opening mechanism to make it work.
If the little black doodah, that pops up and down to show locked and unlocked, actually pops up even for a micro second you may be able to yank on the handle provided you time it right.
From outside I'd say it can only be one of two things, the lock not unlocking or the handle not actuating the door release lever.
From inside it could be the child lock and I did have a case where the same door on mine would not respond to making the child lock "open from inside". But it did still open from outside.
Best of luck mate.