7.2.7: Part 1, Replace a Letter "Write a function named replace_at_index that takes a string and an integer. The function should return a new string that is the same as the old string, EXCEPT with a dash in place of whatever character was at the index indicated by the integer.

Call your function on the word eggplant and the index 3, like this:

s = replace_at_index("eggplant", 3)
You should then print the value of s, which should display:

egg-lant"