Set decoder in Chirpstack's sends among other keys, key: Object and value like {"temp":158,"humidity":"0.00"} how to have key temp and key humidity with their values instead of having them in one single key named object?

tried using a rule chain and a script node placed after input node. the code for the script sofar:

var data = msg;
var keys=Object.keys(data);
var result={};
keys.forEach(function(key){
    result[key]=data[key];
});    
return{msg: result};