Final answer:
To adjust the value of num_users based on update_direction, use the conditional expression: num_users = num_users + 1 if update_direction == 3 else num_users - 1.
Step-by-step explanation:
To increment num_users if update_direction is 3 and decrement num_users otherwise, you would use the following conditional expression:
num_users = num_users + 1 if update_direction == 3 else num_users - 1
This means that if update_direction equals 3, one will be added to num_users. If update_direction is anything other than 3, one will be subtracted from num_users. Thus, for the sample inputs 8 and 3, num_users would be incremented by 1.
The correct statement to increment num_users if update_direction is 3 is:
num_users = num_users + 1 if update_direction == 3 else num_users - 1
This conditional expression first checks if update_direction is equal to 3. If it is, then num_users is incremented by 1. If it is not, then num_users is decremented by 1.