Added missing import.

pes_to_spec/model.py

@@ -21,6 +21,7 @@ from sklearn.model_selection import train_test_split
 from sklearn.base import clone, MetaEstimatorMixin
 from joblib import Parallel, delayed
 from functools import partial
+import multiprocessing as mp
 
 from typing import Any, Dict, List, Optional, Union, Tuple