Update the consumed capacity metrics

def _update_capacity(self, data):
        """ Update the consumed capacity metrics """
        if 'ConsumedCapacity' in data:
            # This is all for backwards compatibility
            consumed = data['ConsumedCapacity']
            if not isinstance(consumed, list):
                consumed = [consumed]
            for cap in consumed:
                self.capacity += cap.get('CapacityUnits', 0)
                self.table_capacity += cap.get('Table',
                                               {}).get('CapacityUnits', 0)
                local_indexes = cap.get('LocalSecondaryIndexes', {})
                for k, v in six.iteritems(local_indexes):
                    self.indexes.setdefault(k, 0)
                    self.indexes[k] += v['CapacityUnits']
                global_indexes = cap.get('GlobalSecondaryIndexes', {})
                for k, v in six.iteritems(global_indexes):
                    self.global_indexes.setdefault(k, 0)
                    self.global_indexes[k] += v['CapacityUnits']