public static MethodInfo Average_NullableDecimal_TSource_2(Type TSource) =>
(s_Average_NullableDecimal_TSource_2 ??
(s_Average_NullableDecimal_TSource_2 = new Func<IQueryable<object>, Expression<Func<object, decimal?>>, decimal?>(Queryable.Average).GetMethodInfo().GetGenericMethodDefinition()))
.MakeGenericMethod(TSource);