Move to TF only

src/transformers/__init__.py

@@ -134,7 +134,6 @@ _import_structure = {
         "is_tensorboard_available",
         "is_wandb_available",
     ],
-    "keras_callbacks": [],
     "modelcard": ["ModelCard"],
     "modeling_tf_pytorch_utils": [
         "convert_tf_weight_name_to_pt_weight_name",
@@ -1279,6 +1278,7 @@ if is_tf_available():
     _import_structure["benchmark.benchmark_args_tf"] = ["TensorFlowBenchmarkArguments"]
     _import_structure["benchmark.benchmark_tf"] = ["TensorFlowBenchmark"]
     _import_structure["generation_tf_utils"] = ["tf_top_k_top_p_filtering"]
+    _import_structure["keras_callbacks"] = []
     _import_structure["modeling_tf_outputs"] = []
     _import_structure["modeling_tf_utils"] = [
         "TFPreTrainedModel",