Manipulating Strings With String Methods – Real Python

31 essential String methods in Python you should know - Python Engineer

String Slicing – Real Python

Python: Compute sum of digits of a given string - w3resource

What is Palindrome in Python? Codes, Algorithms, and more

(Business: check ISBN-10) An ISBN-10 (International Standard Book Number) consists of 10 digits: The last digit, is a checksum, which is calculated from the other nine digits using the following formula: If the checksum is 10, the last digit is denoted as X, according to the ISBN convention. Write a program that prompts the user to enter the first 9 digits as a string and displays the 10-digit ISBN (including leading zeros). Your program should read the input as a string. Here are sample runs: |

Guide To String Formatting In Python | Simplilearn

Python String - GeeksforGeeks

Python String format() Tutorial