public static bool TryGetClassification(HKQuantity value, out HKAppleWalkingSteadinessClassification?classification, out NSError?error)
        {
            if (value == null)
            {
                throw new ArgumentNullException(nameof(value));
            }
            classification = null;

            error = null;
            if (HKAppleWalkingSteadinessClassificationForQuantity(value.GetHandle(), out var classificationOut, out var errorPtr))
            {
                classification = (HKAppleWalkingSteadinessClassification)(long)classificationOut;
                error          = Runtime.GetNSObject <NSError> (errorPtr, false);
                return(true);
            }
            return(false);
        }