App 2: To-Do List Manager / Build the to-do app
Lesson 5 of 10
Picking a task by number
Done and delete both need the user to choose a task number. Write one helper that asks, checks it's valid, and returns the list position (or None).
Key points
- Users count from 1, lists from 0
- Validate before using
- One helper, used twice
def pick_task():
list_tasks()
num = input("Number: ").strip()
if num.isdigit() and 1 <= int(num) <= len(tasks):
return int(num) - 1
print("That number isn't on the list.")
return NoneYour turn
Write pick_task() and test it with good and bad numbers.
Quiz · +10 XP
If the user types 1, which list index does pick_task return?
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