What's the correct way to handle errors with try/except on my code?

Question

I'm trying to handle a "ValueError" (in case, for example, a user type "one" instead of "1") without success. Could you please help? Here is my code:

# collatz sequence
def collatz(number):
    if number %2 == 0: # nbre pair
        print(number // 2)
    elif number % 2 ==1 :  # nbre impair
        print(3 * number + 1)


number = int(input('Type a number of your choice: ')) # for example, enter the followings numbers 3 10 5 16 8 4 2 1

try:   
    collatz(number)
except ValueError :
    print('Please,type an integer.')       

later on, I wrote the 'try/except' inside the function, but it still didn't work.