@interface HKFeatureAvailabilityRequirementBloodOxygenMeasurementsAreEnabled : HKFeatureAvailabilityRequirementBooleanUserDefaultEvaluator + (id)requirementIdentifier; - (id)requirementDescription; - (id)init; - (BOOL)defaultValueWhenKeyIsMissing; - (id)whichUserDefaultsDataSourceInDataSource:(id)a0; - (BOOL)isSatisfiedForBoolValue:(BOOL)a0; @end