function (error, response) {
     if (!_.isNull(error)) {
         callback(error, null);
     } else {
         var result = getItemFromResponse(response);
         result = Platform.allowPlatformToMutateOriginal(instance, result);
         callback(null, result);
     }
 });
 function (error, response) {
     if (!_.isNull(error)) {
         setServerItemIfPreconditionFailed(error);
         callback(error);
     } else {
         var result = getItemFromResponse(response);
         result = Platform.allowPlatformToMutateOriginal(instance, result);
         callback(null, result);
     }
 });
            function (error, response) {
                if (!_.isNull(error)) {
                    callback(error, null);
                } else {
                    var result = _.fromJson(response.responseText);
                    if (Array.isArray(result)) {
                        result = result[0]; //get first object from array
                    }

                    if (!result) {
                        var message =_.format(
                            Platform.getResourceString("MobileServiceTable_NotSingleObject"),
                            idPropertyName);
                        callback(_.createError(message), null);
                    }

                    result = Platform.allowPlatformToMutateOriginal(instance, result);
                    callback(null, result);
                }
            });