Build and validate a binary classifier

Below is a complete implementation that uses only scikit-learn (plus pandas/numpy for data handling). Replace the internals of NumericImputer and CategoricalImputer with your own functions from the previous question if they differ. 1. Imputers and preprocessing Define feature lists: Build the preprocessing pipeline: 2. Define the two candidate models 3. Group-aware development/validation split Hold out a final validation set grouped by user_id. This held-out set is never…