public Task <List <T> > FindByPropertyAsync(string propertyName, object propertyValue)
        {
            Expression <Func <T, bool> > predict = DynamicQueryExpressions <T> .GetExpresionTrees(propertyName, propertyValue);

            return(FindAsync(predict));
        }
        public List <T> FindByProperty(string propertyName, object propertyValue)
        {
            Expression <Func <T, bool> > predict = DynamicQueryExpressions <T> .GetExpresionTrees(propertyName, propertyValue);

            return(Find(predict).ToList());
        }