Required pull request for checking the LabWork 1 and 2

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Try using the construction given below instead of these static constants.

+ (NSArray *)descriptions
{
    static NSArray *genderNames = nil;
    static dispatch_once_t onceToken = 0;
    dispatch_once(&onceToken, ^{
        genderNames =  @[@"Undefined gender", @"Male", @"Female"];
    });

    return genderNames;
}