title: experimental_list_devices attribute missing in tensorflow_core._api.v2.config
body: <p>Am using tensorflow 2.1 on Windows 10. On running</p>
  <pre><code>model.add(Conv3D(16, (22, 5, 5), strides=(1, 2, 2), padding='valid',activation='relu',data_format= &quot;channels_first&quot;, input_shape=input_shape))
  
  </code></pre>
  <p>on spyder, I get the this error:</p>
  <pre><code>{ AttributeError: module 'tensorflow_core._api.v2.config' has no attribute 'experimental_list_devices' }
  </code></pre>
  <p>How can I solve this error?</p>