9. lllan'alJles and refer to s. The expression returns the index of the rst occurrence of . The expression returns the index of the rst occurrence of . starting at index within . {See for more info] Write an expression that produces the index of the second occurrence of in . If does not occur twice in , the expression should produce . Unlike , you should allow overlapping occurrences of . For example, if is and is , your expression should return . If is and is , your expression should return . Your answer must. be a single expression that does not use square brackets [string indexing and slicing}, and you can only call method and use the arithmetic operators [1-, -, etc.]- Hint: call twice in your expression. I Enter answer here