title: TensorFlow Lite: Init node doesn't exist
body: <p>I was trying to convert a model in a Keras file (.h5) to a TensorFlow Lite file (.tflite) using the following codes:</p>
  
  <pre><code># Save model as .h5 keras file
  keras_file = "eSleep.h5"
  model_save = tf.keras.models.save_model(model,keras_file,overwrite=True,include_optimizer=True)
  
  # Export keras file to TensorFlow Lite model
  converter = tf.lite.TFLiteConverter.from_keras_model_file(keras_file)
  tflite_model = converter.convert()
  open("eSleep.tflite", "wb").write(tflite_model)
  </code></pre>
  
  <p>However, the following line:</p>
  
  <pre><code>tflite_model = converter.convert()
  </code></pre>
  
  <p>returned errors:</p>
  
  <pre><code>I tensorflow/core/grappler/devices.cc:53] Number of eligible GPUs (core count &gt;= 8): 0 (Note: TensorFlow was not compiled with CUDA support)
  I tensorflow/core/grappler/clusters/single_machine.cc:359] Starting new session
  E tensorflow/core/grappler/grappler_item_builder.cc:636] Init node dense/kernel/Assign doesn't exist in graph
  </code></pre>
  
  <p>Can anybody help me to understand what does "Init node dense/kernel/Assign doesn't exist in graph" means and how to fix the error?</p>