
    Design a function for the friend recommendation system that extracts the interest category code from each user profile string, where the code is always represented by the last character of the profile string. The extracted codes will be used to match users with similar interests and enhance the recommendation accuracy.
    

    
def extract_rear(test_tuple):
    """
    Design a function for the friend recommendation system that extracts the interest category code from each user profile string, where the code is always represented by the last character of the profile string. The extracted codes will be used to match users with similar interests and enhance the recommendation accuracy.
    

    """
def extract_rear(test_tuple):
    """
    Design a function for the friend recommendation system that extracts the interest category code from each user profile string, where the code is always represented by the last character of the profile string. The extracted codes will be used to match users with similar interests and enhance the recommendation accuracy.
    

    """
    res = list((sub[len(sub) - 1] for sub in test_tuple))
    return res