I have the following Mantle object & want to convert the dictionary to Mantle object. but the conversion always returns empty MTLModel object.
Any ideas?

```
//ABC.h

@interface ABC : MTLModel<MTLJSONSerializing>

@property (nonatomic, strong) NSString *Identifier;
@property (nonatomic, strong) NSString *Name;
@property (nonatomic, strong) NSString *ImageURLString;
@property (nonatomic, strong) NSString *Desc;
@property (nonatomic, strong) NSString *lastUpdated;

@end

// ABC.m

@implementation ABC

+ (NSDictionary *)JSONKeyPathsByPropertyKey {

    return @{
             @"Identifier" : @"id",
             @"Name" : @"name",
             @"Desc" : @"desc",
             @"ImageURLString" : @"image_url",
             @"lastUpdated" : @"last_updated_at"
             };
}

@end

```

Calling code:

```
ABC *abc = [MTLJSONAdapter modelOfClass:ABC.class fromJSONDictionary:tempDict error:NULL]; 

```

The JSON dictionary is:

```
{
    desc = "asdadasdakjqewqwmsdnasdaksdasd";
    id = adsasdasdasdasd;
    "image_url" = "http://upload.wikimedia.org/wikipedia/commons/thumb/1/19/abc.JPG";
    "last_updated_at" = "2015-07-25 04:22:39.851710";
    name = asdasdqwe;
}

```

The result ABC object has no contents. Can't figure what I am missing here.

Any ideas???