Python, TypeError: 'NoneType' object is not subscriptable

Function code:

def randomize_poll_winner(connection):
    poll_id = int(input("Enter poll you'd like to pick a winner for: "))
    poll_options = database.get_poll_details(connection, poll_id)
    _print_poll_options(poll_options)

    option_id = int(input("Enter which is the winning option, we'll pick a random winner from 
    voters:"))
    winner = database.get_random_poll_vote(connection, option_id)
    print(f"The randomly selected winner is {winner[0]}.")

Second important function:

def get_random_poll_vote(connection, option_id):
with connection:
    with connection.cursor() as cursor:
        cursor.execute(SELECT_RANDOM_VOTE, (option_id,))
        cursor.fetchone()

SQL code:

SELECT_RANDOM_VOTE = "SELECT * FROM votes WHERE option_id = %s ORDER BY RANDOM() LIMIT 1"

Logs:

    Traceback (most recent call last):
  File "D:\Programming\Python\Python+PostgreSQL_2.0\poll_app\app.py", line 108, in <module>
    menu()
  File "D:\Programming\Python\Python+PostgreSQL_2.0\poll_app\app.py", line 103, in menu
    MENU_OPTIONS[selection](connection)
  File "D:\Programming\Python\Python+PostgreSQL_2.0\poll_app\app.py", line 76, in randomize_poll_winner
    print(f"The randomly selected winner is {winner[0]}.")
TypeError: 'NoneType' object is not subscriptable