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

### Tell us what’s happening:

Hey there,
I have a problem understanding the task as I am not sure which variable I am assigned to Print.

``````
# 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 odd_digits in card_number:
print(odd_digits)
#mistake?

# 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

as per the instruction u need to use `odd_digits`.

correct syntax is

``````for variable in list:
statement1
.
.
statementn
``````

replace list with `odd_digits` and print variable

I thought I was using odd_digits?

instead of i u can use any variable and just print that variable. normally we use i,j,k in that flow i wrote `i` but u can use any variable

in the instruction given odd_digits contain values and u need to access it and print it. not use odd_digits as a variable to access the list. here odd_digit is the list. hope u got it

2 Likes

got it now! thank you! dumb mistake lol :))

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