1_cust_churn_dataprep.ipynb failed CI

Link to the notebook:
https://github.com/aws/amazon-sagemaker-examples/blob/master/use-cases/customer_churn/1_cust_churn_dataprep.ipynb

Error:

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Exception encountered at "In [5]":
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NameError Traceback (most recent call last)
in
----> 1 processing_output_filename

NameError: name 'processing_output_filename' is not defined

Open use-cases/customer_churn/1_cust_churn_dataprep.ipynb and inspect the cells before the reported failure at In [5]. Run the notebook through the CI check to reproduce the undefined processing_output_filename error. Done means the notebook completes without this NameError and CI passes.

Written by the indexing model from the issue text.