2c) Split the MR_tfidf_X and MR_y into training set and test set. Name these variables as: MR_train_tfidf_X and MR_train_tfidf_y for the training set MR_test_tfidf_X and MR_test_tfidf_y for the test set We will use the same 80/20 split as in part 1. You can use the same num_training variable from part 1 to split up the data.