PYTHON

The last digit of a credit card number is the check digit, which protects against transcription errors such as an error in a single digit or switching two digits.

The following method is used to verify actual credit card numbers but, for simplicity, we will describe it for numbers with 8 digits instead of 16:

• Starting from the rightmost digit, form the sum of every other digit. For example, if the credit card number is 4358 9795, then you form the sum 5 + 7 + 8 + 3 = 23.

• Double each of the digits that were not included in the preceding step. Add all of the digits of the resulting numbers. For example, with the number given above, doubling the digits. starting with the next-to-last one, yields 18 18 10 8. Adding all digits in these values yields 1 + 8 + 1 + 8 + 1 + 0 + 8 = 27.

• Add the sums of the two preceding steps. If the last digit of the result is 0, the number is valid. In our case, 23 + 27 = 50, so the number is valid.

• Write a program that implements this algorithm.
  • Do not use/import a pre-fab luhn method.

Requirements

1. Prompt the user for an 8 digit number
   1. Ensure the data actually is a number
   2. Ensure the data actually is 8 digits long
2. Dont let the user proceed if a and b arent true; prompt them until they get it right!
3. Print out whether the number is valid or not
   • If it is not valid, you should print the value of the check digit that would make it valid