As far as i know, it's not possible to do that.
In fact I hope that such a thing is not possible, as it would've strange consequents, like what happens if an other file tries to access that information in that moment.
I would suggest that you save player specific vars in the player node/object.
But if you want to do it in a global object, you could just create a reset
function, allĂ :
func reset():
health = deafaultVal
mana = defaultVal
etc
And just call that, instead of using var mana = defaultVal