Python Do not use the len function in the program Develop a program that allows the user to enter a string. It then prints a table of the letters of the alphabet in alphabetical order which occur in the string together with the percentage of each letter occurs. Case should be ignored. A sample run of the program might look this this: Please enter a sentence: This is String g 8.3% h 8.3% i 25.0% n 8.3% r 8.3% s 25.0% t 16.6%