AttributeError: module 'tensorflow.python.keras.utils.tf_utils' has no attribute 'smart_cond'

[thomastiotto]

I've been experimenting with the pre-release tensorflow_macos package and, while I've managed to install and import nengo-dl, I'm getting the following error on execution. I seem to remember the same exact error popping up when nengo-dl<3.3.0 and tensorflow==2.3.0 were used in conjunction.
My current setup is the following:

conda list | grep "nengo"
nengo                     3.0.0                    pypi_0    pypi
nengo-dl                  3.3.0                    pypi_0    pypi

pip list | grep "tensorflow"
tensorflow             2.4.0rc2
tensorflow-addons      0.11.2
tensorflow-estimator   2.4.0rc2
tensorflow-macos       0.1a0

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/Applications/PyCharm.app/Contents/plugins/python/helpers/pydev/_pydev_bundle/pydev_umd.py", line 197, in runfile
    pydev_imports.execfile(filename, global_vars, local_vars)  # execute the script
  File "/Applications/PyCharm.app/Contents/plugins/python/helpers/pydev/_pydev_imps/_pydev_execfile.py", line 18, in execfile
    exec(compile(contents+"\n", file, 'exec'), glob, loc)
  File "/Users/thomastiotto/PycharmProjects/Learning-to-approximate-functions-using-niobium-doped-strontium-titanate-memristors/experiments/learn_multidimensional_functions.py", line 199, in <module>
    with nengo_dl.Simulator( learned_model_mpes, device=device ) as sim_mpes:
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/simulator.py", line 530, in __init__
    self._build_keras(progress)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo/utils/magic.py", line 181, in __call__
    return self.wrapper(self.__wrapped__, self.instance, args, kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/simulator.py", line 57, in with_self
    output = wrapped(*args, **kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/simulator.py", line 553, in _build_keras
    outputs = self.tensor_graph(inputs, stateful=self.stateful, progress=progress)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/keras/engine/base_layer.py", line 946, in __call__
    return self._functional_construction_call(inputs, args, kwargs,
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/keras/engine/base_layer.py", line 1085, in _functional_construction_call
    outputs = self._keras_tensor_symbolic_call(
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/keras/engine/base_layer.py", line 817, in _keras_tensor_symbolic_call
    return self._infer_output_signature(inputs, args, kwargs, input_masks)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/keras/engine/base_layer.py", line 858, in _infer_output_signature
    outputs = call_fn(inputs, *args, **kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/autograph/impl/api.py", line 620, in wrapper
    return func(*args, **kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/tensor_graph.py", line 476, in call
    self._build_loop(sub) if self.use_loop else self._build_no_loop(sub)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/tensor_graph.py", line 626, in _build_loop
    loop_vars = tf.while_loop(
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/util/deprecation.py", line 605, in new_func
    return func(*args, **kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/ops/control_flow_ops.py", line 2489, in while_loop_v2
    return while_loop(
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/ops/control_flow_ops.py", line 2687, in while_loop
    return while_v2.while_loop(
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/ops/while_v2.py", line 192, in while_loop
    body_graph = func_graph_module.func_graph_from_py_func(
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/framework/func_graph.py", line 990, in func_graph_from_py_func
    func_outputs = python_func(*func_args, **func_kwargs)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/tensorflow/python/ops/while_v2.py", line 178, in wrapped_body
    outputs = body(*_pack_sequence_as(orig_loop_vars, args))
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/tensor_graph.py", line 603, in loop_body
    loop_i = self._build_inner_loop(loop_i, update_probes, progress)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/tensor_graph.py", line 773, in _build_inner_loop
    side_effects = self.op_builder.build_step(self.signals, progress)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/builder.py", line 101, in build_step
    output = self.op_builds[ops].build_step(signals)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/neuron_builders.py", line 531, in build_step
    self.built_neurons.build_step(signals)
  File "/Users/thomastiotto/opt/anaconda3/envs/tf_mac/lib/python3.8/site-packages/nengo_dl/neuron_builders.py", line 191, in build_step
    tf_utils.smart_cond(
AttributeError: module 'tensorflow.python.keras.utils.tf_utils' has no attribute 'smart_cond'

[drasmuss]

TensorFlow 2.4.0rc0 moves the location of smart_cond. If you use the current master version of NengoDL it should be compatible with the 2.4 pre-release (pip install git+https://github.com/nengo/nengo-dl). We should also be doing a new NengoDL release in the next day or two that will contain that update.