Dictionary keys sorted as they came in http response with Mantle

Question

You parse a property as a NSDictionary object in a MTLModel object, and then, you get the keys with allkeys method.

@interface SomeModel : MTLModel<MTLJSONSerializing>

@property (copy, nonatomic, readonly) NSDictionary *dictionary;

@end

...

NSArray *keys = [dictionary allkeys];

The returned keys are not usually sorted the same way they came in the HTTP response body.

For instance, the http response is this:

{"someObject":{"key1": "valueOfKey1", "key2": "valueOfKey2", "key3": "valueOfKey3",}}

but then, the NSDictionary keys are returned like this:

{"key2", "key1", "key3"}

How can you get the keys sorted as they came?

I have personally tested this, but it doesn't work:

[[dict allKeys] sortedArrayUsingSelector: @selector(compare:)];