Python based interpretation of the Luhn Algorithm.
Program checks if the credit card inputted is valid or not.
Reverse the order of the credit card numbers.
Take the digits found in the odd places of the reversed credit card number.
Add those numbers and create a variable named s1.
Take the digits found in the even places of the reversed credit card number.
Multiply these digits each by 2.
Record the digits if they are >9 to create partial sums. Otherwise keep the new number.
Sum up the new partial numbers or regular numbers*2 to create a variable named s2.
If s1 + s2 = a number ending with 0 -> VALID or else -> FAKE