# Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 19

### Tell us what’s happening:

Not sure that I am understanding the question that is being asked.

I added a for loop and I want all digits from the odd_digit list, should I be saying all digit?

### Your code so far

``````
# User Editable Region

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:
print(digit)

# User Editable Region

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

verify_card_number(translated_card_number)

main()
``````

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### Challenge Information:

Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 19

The loop should be inside the function.

Do you mean inside the

def verify_card_number(card_number):

Am I putting it at the end of the " : " or inside the ( )

It should be inside the `verify_card_number` function. `odd_digits` exists only inside that function.

1 Like

To add to what Dario_DC mentioned, you control what block of code is in a function by using indentation.