Finding last occurrence of substring in string, replacing that

Question

So I have a long list of strings in the same format, and I want to find the last \".\" character in each one, and replace it with \". - \". I\'ve tried using rfind, but I can\'t

Answer 1

a = "A long string with a . in the middle ending with ."

# if you want to find the index of the last occurrence of any string, In our case we #will find the index of the last occurrence of with

index = a.rfind("with") 

# the result will be 44, as index starts from 0.