# Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 33

### Tell us what’s happening:

Although my code runs fine I am unable to complete the task…
Another question of mine is why I wasn’t able to use

if total == 0:
print('VALID!')

Thanks in advance, Jonas

### Your code so far

def verify_card_number(card_number):
sum_of_odd_digits = 0
card_number_reversed = card_number[::-1]
odd_digits = card_number_reversed[::2]

for digit in odd_digits:
sum_of_odd_digits += int(digit)

sum_of_even_digits = 0
even_digits = card_number_reversed[1::2]
for digit in even_digits:
number = int(digit) * 2
if number >= 10:
number = (number // 10) + (number % 10)
sum_of_even_digits += number
total = sum_of_odd_digits + sum_of_even_digits
print(total)

# User Editable Region

return total % 10 == 0
def main():
card_number = '4111-1111-4555-1142'
card_translation = str.maketrans({'-': '', ' ': ''})
translated_card_number = card_number.translate(card_translation)

if verify_card_number(translated_card_number) == 0: #I thought that if x== 0; x = true
print('VALID!')
else:
print('INVALID!')

# User Editable Region

main()

### Your browser information:

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### Challenge Information:

Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 33

here u don’t need to use ==0 because in return from verify_card_number it already returns true or false

this returns true or false

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