public async Task <int> SumAsync(IEnumerable <KeyValuePair <Attribute, int> > rawAttributes, Attribute attribute)
{
var tmp = rawAttributes.GroupBy(x => x.Key);
var ret = tmp.Where(x => x.Key == attribute).Select(x => x.Sum(y => y.Value));
return(await Task.FromResult(ret.FirstOrDefault()).ConfigureAwait(false));
}
public int Sum(IEnumerable <KeyValuePair <Attribute, int> > rawAttributes, Attribute attribute) => SumAsync(rawAttributes, attribute).Result;