Entity Framework Stumped by GroupBy
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In the code below, `detail` is a list of `{ User, Amount, <other fields> }`, as in

    var detail = new List<TuitionDetailItem>();

What I'd like is for `perMember` to be a list of `{ User, Total }` where the floats are the sums over `Amount` for each `User`.

    var perMember = detail
        .Where(x => x.ItemType == TuitionDetailItemType.Details)
        .GroupBy(x => new { x.User, x.Amount })
        .Select(x => new { x.Key.User, Total = x.Sum(y => y.Amount) })
        .ToList();

What I actually get is just a copy of `detail` with no grouping or summing.

Thanks for help!!
Eric