private async Task <List <Symptom> > GetSymptomsByIds(ICollection <Symptom> symptoms)
        {
            var symptomsIds = symptoms
                              .Select(x => x.SymptomId)
                              .AsEnumerable();

            return(await Symptoms
                   .Where(x => symptomsIds.Contains(x.SymptomId))
                   .ToListAsync());
        }
        public async ValueTask <bool> DeleteSymptomsAsync(List <int> symptoms)
        {
            var contextSymptoms = Symptoms
                                  .Where(x => symptoms.Contains(x.SymptomId))
                                  .AsEnumerable();

            Symptoms.RemoveRange(contextSymptoms);

            await SaveChangesAsync();

            return(true);
        }