Question

Your program has a dictionary called classes. The keys in classes are teacher's last names (as strings), and the corresponding values are the number of students in that teacher's class. For example, if Mr. Brown has 17 students in her class, then 'Brown' might be a key in classes with a corresponding value of 17. Write a few lines in Python that will do the following:

• Ask the user to enter the last name of a teacher
• IF that last name is a key in your dictionary, add one to its value (e.g., if the value was 17, you would update it to be 18)
• If that last name is not a key in your dictionary, print 'Error'

Answer 1

# Note: Assuming that classes dictionary is already included in the program
# And I am proving only the statements asked for in the question
# Ask the user to enter the last name of a teacher
last_name = input("Enter last name of a teacher: ")
# IF that last name is a key in your dictionary,
if last_name in classes:
    # add one to its value (e.g., if the value was 17, you would update it to be 18)
    classes[last_name] += 1
# If that last name is not a key in your dictionary,
else:
    # print 'Error'
    print('Error')