Is there a better way to mask a Credit Card number in python?

Question

So I have a csv file that contains full credit-card numbers.. We dont need the full number, and so I am writing a quick script to parse through the csv and replace the cc number with a masked representation. (all *'s except the last four). I am pretty new to python and hacked this up, and it works, but in order to learn I want to know if it could be done easier.

Assume that "str" will be a full creditcard number. But for the sake of my example I am just using the string "CREDITCARDNUMBER".

str = "CREDITCARDNUMBER";
strlength = len(str)
masked = strlength - 4
slimstr = str[masked:]
print "*" * masked + slimstr

The output is exactly what I want

************MBER

But I am sure there is a more elegant solution. :) Thanks!

Answer 1

For those who want to keep Issuer Identification Number (IIN) (previously called the "Bank Identification Number" (BIN)), which is usually the first 6 digits, that should do the job:

print card[:6] + 'X' * 6 + card[-4:]
'455694XXXXXX6539'