In this task, you need to replace a letter in the sentence with another given letter.

Ex Input:
Sentence: 'a person jumping up in the air on a snowboard'. Replace the letter 'r' with 'o' in the sentence.

Ex Output:
a peoson jumping up in the aio on a snowboaod


Ex Input:
Sentence: 'a couple of giraffes being feed by people at the zoo'. Replace the letter 't' with 'v' in the sentence.

Ex Output:
a couple of giraffes being feed by people av vhe zoo


Ex Input:
Sentence: 'a couple carrying their luggage off of a train'. Replace the letter 'a' with 'u' in the sentence.

Ex Output:

u couple currying their lugguge off of u truin