Required pull request for checking the LabWork 1 and 2

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Hoh, I saw some similar syntax in other realisations of Singleton when searched for objective-c implementations of this pattern) As I understand, + method returns only one constantly NSArray with 3 NSString-records, and we can just obtain require string from array for index-genderId.
So, I'll go to read about dispatch_once() and ^{ syntax)