How to predict probabilities from a new data set from an already built and validated model in Python?
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You should apply the same steps 1-3 to the new dataset as you did to the original train and test datasets. Smote is a special case and couldn't be applied anyway as you don't have the response in the new dataset. In general, your train, test, validate, and any new datasets should go through the same data pre-processing. The new dataset will replace your Test dataset in your prediction.
There may be more steps you can add, but the current arrangement is fine.