Fix Keras serialization naming collision (#2001)

* Structure for Namex export

* Switch to programmatic API generation with Namex

* Fix missing import

* Fix preset class names

* Fix serialization collision

Author: ianstenbit

keras_cv/api_export.py

@@ -22,27 +22,28 @@
     namex = None
 
 
-def maybe_register_serializable(symbol):
+def maybe_register_serializable(symbol, package):
     if isinstance(symbol, types.FunctionType) or hasattr(symbol, "get_config"):
-        keras.saving.register_keras_serializable(package="keras_cv")(symbol)
+        keras.saving.register_keras_serializable(package=package)(symbol)
 
 
 if namex:
 
     class keras_cv_export(namex.export):
-        def __init__(self, path):
+        def __init__(self, path, package="keras_cv"):
             super().__init__(package="keras_cv", path=path)
+            self.package = package
 
         def __call__(self, symbol):
-            maybe_register_serializable(symbol)
+            maybe_register_serializable(symbol, self.package)
             return super().__call__(symbol)
 
 else:
 
     class keras_cv_export:
-        def __init__(self, path):
-            pass
+        def __init__(self, path, package="keras_cv"):
+            self.package = package
 
         def __call__(self, symbol):
-            maybe_register_serializable(symbol)
+            maybe_register_serializable(symbol, self.package)
             return symbol

keras_cv/layers/feature_pyramid.py

@@ -17,8 +17,6 @@
 from keras_cv.api_export import keras_cv_export
 
 
-# TODO(scottzhu): Register it later due to the conflict in the retinanet
-# @keras.utils.register_keras_serializable(package="keras_cv")
 @keras_cv_export("keras_cv.layers.FeaturePyramid")
 class FeaturePyramid(keras.layers.Layer):
     """Implements a Feature Pyramid Network.

keras_cv/models/object_detection/retinanet/feature_pyramid.py

@@ -17,7 +17,10 @@
 from keras_cv.backend import ops
 
 
-@keras_cv_export("keras_cv.models.retinanet.FeaturePyramid")
+@keras_cv_export(
+    "keras_cv.models.retinanet.FeaturePyramid",
+    package="keras_cv.models.retinanet",
+)
 class FeaturePyramid(keras.layers.Layer):
     """Builds the Feature Pyramid with the feature maps from the backbone."""