# import necessary libraries
import pandas as pd

# suppose you have following train & test sets
X_train = pd.DataFrame({'col':['A', 'B', 'C', 'B']})
X_test = pd.DataFrame({'col':['A', 'C', 'D']})

# print the train & test sets
print(f"Feature 'col' of training set: \n{X_train}")
print(f"\nFeature 'col' of testing set: \n{X_test}")