AttributeError: 'Operation' object has no attribute '_c_op'

[888yyh]

tensorflow2.1 dear professor, i met this error,hope you could help me.Thank you. Traceback (most recent call last): File "run.py", line 118, in imgs_mask_test = model.predict(imagestest, verbose=1) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training.py", line 1013, in predict use_multiprocessing=use_multiprocessing) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2.py", line 498, in predict workers=workers, use_multiprocessing=use_multiprocessing, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2.py", line 475, in _model_iteration total_epochs=1) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2.py", line 128, in run_one_epoch batch_outs = execution_function(iterator) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 98, in execution_function distributed_function(input_fn)) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/def_function.py", line 568, in call result = self._call(*args, **kwds) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/def_function.py", line 615, in _call self._initialize(args, kwds, add_initializers_to=initializers) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/def_function.py", line 497, in _initialize *args, **kwds)) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/function.py", line 2389, in _get_concrete_function_internal_garbage_collected graph_function, _, _ = self._maybe_define_function(args, kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/function.py", line 2703, in _maybe_define_function graph_function = self._create_graph_function(args, kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/function.py", line 2593, in _create_graph_function capture_by_value=self._capture_by_value), File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/framework/func_graph.py", line 978, in func_graph_from_py_func func_outputs = python_func(*func_args, **func_kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/eager/def_function.py", line 439, in wrapped_fn return weak_wrapped_fn().wrapped(*args, **kwds) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 85, in distributed_function per_replica_function, args=args) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 763, in experimental_run_v2 return self._extended.call_for_each_replica(fn, args=args, kwargs=kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 1819, in call_for_each_replica return self._call_for_each_replica(fn, args, kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 2164, in _call_for_each_replica return fn(*args, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/autograph/impl/api.py", line 292, in wrapper return func(*args, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 212, in _predict_on_batch result = predict_on_batch(model, x) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 556, in predict_on_batch return predict_on_batch_fn(inputs) # pylint: disable=not-callable File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/base_layer.py", line 778, in call outputs = call_fn(cast_inputs, *args, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/network.py", line 717, in call convert_kwargs_to_constants=base_layer_utils.call_context().saving) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/network.py", line 891, in _run_internal_graph output_tensors = layer(computed_tensors, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/engine/base_layer.py", line 778, in call outputs = call_fn(cast_inputs, *args, **kwargs) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/keras/layers/convolutional.py", line 209, in call outputs = self._convolution_op(inputs, self.kernel) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/ops/nn_ops.py", line 1135, in call return self.conv_op(inp, filter) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/ops/nn_ops.py", line 640, in call return self.call(inp, filter) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/ops/nn_ops.py", line 616, in _with_space_to_batch_call block_shape=self.dilation_rate) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/ops/array_ops.py", line 3303, in required_space_to_batch_paddings const_block_shape = tensor_util.constant_value(block_shape) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/framework/tensor_util.py", line 827, in constant_value ret = _ConstantValue(tensor, partial) File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/framework/tensor_util.py", line 673, in _ConstantValue if tensor.op.type == "Const": File "/home/ma-user/anaconda3/envs/TensorFlow-2.1.0/lib/python3.7/site-packages/tensorflow_core/python/framework/ops.py", line 2220, in type return c_api.TF_OperationOpType(self._c_op) AttributeError: 'Operation' object has no attribute '_c_op'