Calculating area in Google Earth Engine || Part-2/3

[@maesamnamdari]

Hi Sir.
I have a question about the video no.2. calculation area in Google Earth
when I want to run the below code,
var classAreas = ee.List(areas.get('groups'))
var classAreaLists = classAreas.map(function(item){
var areaDict = ee.Dictionary(item)
var classNumber = ee.Number(areaDict.get('class')).format()
var area = ee.Number(
areaDict.get('sum')).divide(1000000).round()
return ee.List([classNumber, area])
})
print (classAreaLists)
I come up against Error
Dictionary (Error)
Dictionary.get: Dictionary does not contain key: class.
could you help me?
yours sincerely
meisam namdari

[@soujanyapisipati6260]

Thank you very much!

[@GeoGuru1]

You're welcome!