I extracted test 'customer_id' and 'vendor_id' features from 'CID X LOC_NUM X VENDOR' SampleSubmission column, by splitting the strings using ' X ' as delimiter. Train dataset had customer_id' and 'vendor_id' features already available. I then combined both train and test dataset that was derived from SampleSubmission file and factorized 'customer_id's by using pandas.factorize() function. I then finally split combined, factorized dataset back into train and test sets and used sklearn.train_test_split to get validation subset of training data.

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