supplemental.rb

if data['supplemental_data']    
  sum = {}
  data['supplemental_data'].each_pair do |key, value|
    sum[key] = value.values
  end
  sum
else
  {}
end

#Here is the 'data' json which is converted into hash
#"supplemental_data": {
#  "groups": {
#   "144959": {
#    "id": 144959,
#    "name": "test3",
#    "last_modified": "2013-07-12T15:32:25+00:00",
#    "created": "2013-07-12T15:32:25+00:00"
#   }
#  }
# }