Problem in Python (Try, Finally and Except)

Question

I'm trying to get an accurate age but this doesn't work it gives me errors and sometimes repeats itself. I've been trying to get it to work for hours. But I can't figure it out, I think the problem is in finally. I tried except but it just gives me errors. How should I fix it?

end04 = False                      
while not end04:
    Age = input("Age: ")
    try:
        int(Age)
        end04 = True
    finally:
        if Age[-1:] == 'w':
            Age.replace('w','')
            int(Age)
            Age /= 52
            end04 = True
        elif Age[-1:] == 'm':
            Age.replace('m', '')
            int(Age)
            Age /= 12
            end04 = True
        else:
            end04 = False
            print("Only enter m or w after number or just number")

if I put finally It just repeats saying "Only enter m or w after a number or just number"

If I put except it gives an error (When I enter 3m)

int(Age) ValueError: invalid literal for int() with base 10: '3m'

"*I'm trying to get an accurate age*" -- help us understand what your program is *meant* to do. Please [edit] your question to show intended input & expected output. — costaparas, Feb 14 '21 at 05:45
"*this doesn't work it gives me errors and sometimes repeats itself*" -- what errors do you get when you try to run the code, and with what inputs do these errors occur? Please [edit] your question to show the full error messages. — costaparas, Feb 14 '21 at 05:46
When you do `int(Age)` you aren't assigning the result anywhere. You want `Age = int(Age)`. Similarly for `Age.replace('w','')` and `Age.replace('m', '')`. These functions don't modify `Age`, they return a new value, which you must then assign to `Age`. — costaparas, Feb 14 '21 at 06:08
And you would want to use `except` rather than `finally`. Your program attempts to convert `Age` to an `int` initially, if it fails, it will then go into the `except` clause. The purpose of `finally` is completely different, as [explained here](https://stackoverflow.com/questions/11551996/why-do-we-need-the-finally-clause-in-python). — costaparas, Feb 14 '21 at 06:08
As a complete aside, the [tag:python-requests] tag is completely irrelevant here (that's meant to be used for code that utilizes the `requests` library itself), and I'd argue the [tag:list] tag isn't necessary either. — costaparas, Feb 14 '21 at 06:14

score 1 · Answer 1 · answered Feb 14 '21 at 06:20

end04 = False                      
while not end04:
    Age = input("Age: ")
    try:
        int(Age)
        end04 = True
    except ValueError: # Here your are trying to catch the Exception (when m/w in input), so you need to use except with the Exception you want to catch
        if Age[-1:] == 'w':
            Age = Age.replace('w','') # string.replace function return's the replaced string therefore need to assign it back to Age Variable.
            Age = int(Age) # similarly int() also returns the type casted value.
            Age /= 52
            end04 = True
        elif Age[-1:] == 'm':
            Age = Age.replace('m', '')
            Age = int(Age)
            Age /= 12
            end04 = True
        else:
            end04 = False
            print("Only enter m or w after number or just number")

I have fixed your code.

Do also look into,

string.isnumeric() method returns True if all the characters are numeric (0-9), otherwise False. Try using that instead of using try except.
The finally block lets you execute code, regardless of the result of the try- and except blocks. But in your case you wanted to catch the Exception when there is a character in the input therefore except is appropriate here.

Lohith · Answer 2 · 2021-02-15T14:29:00.550

This is how your final program would look like, in simpler way and handling all sort of inputs.

import re

end04 = False
divider = 1
while not end04:
    Age = input("Age: ")
    try:
        age = re.findall(r'\d+\w', Age)
        if len(age) > 0:
            letter = age[0][-1]
            if letter.isnumeric() or (letter in ['w', 'm']):
                if letter in ['w', 'm']:
                    age = int(age[0][:-1])
                    divider = 12
                    if letter == 'w':
                        divider = 52

                else:
                    age = int(age[0])
                print('age', age)
                age /= divider
                print('output', age)
                end04 = True
    finally:
        if not end04:
            print("Only enter m or w after number or just number")

output:

Age: 32
age 32
output 32.0

Age: 32w
age 32
output 0.6153846153846154

Age: 32m
age 32
output 2.6666666666666665

Problem in Python (Try, Finally and Except)

2 Answers2