AttributeError: module 'tensorflow.tools.api.generator.api.estimator' has no attribute 'BestExporter'

[hailabpucpr]

Hello,
Thank you for the tutorial and code.
When calling the "experiment" method, this error occurs:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-101-775f3aa98789> in <module>
     23     optimizer='Momentum',
     24     lr=0.00001,
---> 25     clip_gradients=20.0
     26 )

<ipython-input-93-92b1f53a9364> in experiment(data_params, **kwargs)
     33     )
     34 
---> 35     best_exporter = tf.estimator.BestExporter(
     36     #best_exporter = tf.estimator.Exporter(
     37       name="best_exporter",

AttributeError: module 'tensorflow.tools.api.generator.api.estimator' has no attribute 'BestExporter'

I tried with several versions of tensorflow, but without success. (1.11, 1.5, 1.8, 2.x)

Could someone help?