7.6 / 10 123... Official
: This method returns the starting index of the first occurrence of letter . If it isn't found, it returns -1 .
: The while True ensures the code keeps searching until every instance is gone, which is necessary if the letter appears multiple times (e.g., removing "na" from "banana"). Alternative (Standard Python) 7.6 / 10 123...
: If letter is an empty string, the loop would run forever; we return the original word immediately. : This method returns the starting index of
