Converting Tensorflow Keras model to ONNX format

import tf2onnx
import onnx

# Example
inputs = Input( (128, 128, 1) ) 

# ... create model with inputs and layers
# ... train model



onnx_model, _ = tf2onnx.convert.from_keras(model, [
  tf.TensorSpec(
    shape=inputs.get_shape(), 
    # If input values are of type is float32
    dtype=tf.float32)
], 
# the opset to be used for the ONNX model, default is the latest
opset=13)