Internal change

PiperOrigin-RevId: 301639338

Author: saberkun

official/vision/image_classification/resnet/resnet_model.py

@@ -255,9 +255,7 @@ def resnet50(num_classes,
     x = img_input
 
   if backend.image_data_format() == 'channels_first':
-    x = layers.Lambda(
-        lambda x: backend.permute_dimensions(x, (0, 3, 1, 2)),
-        name='transpose')(x)
+    x = layers.Permute((3, 1, 2))(x)
     bn_axis = 1
   else:  # channels_last
     bn_axis = 3
@@ -382,8 +380,7 @@ def resnet50(num_classes,
       block='c',
       use_l2_regularizer=use_l2_regularizer)
 
-  rm_axes = [1, 2] if backend.image_data_format() == 'channels_last' else [2, 3]
-  x = layers.Lambda(lambda x: backend.mean(x, rm_axes), name='reduce_mean')(x)
+  x = layers.GlobalAveragePooling2D()(x)
   x = layers.Dense(
       num_classes,
       kernel_initializer=initializers.RandomNormal(stddev=0.01),