Linq 语法 依据某一字段判断数组中是否有重复数据，并且另外一个字段值相加，一个字段值拼接

from m in Productions group m by m.sequence into g select new Production { sequence = g.Key, amount = g.Sum(m => m.amount), name = g.Max(m => m.name), amountSpecified = true, aaaaa= string.Join(",", g.Select(m => m.aaaaa)) }