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

Ex Input:
Sentence: 'a young baseball player throws the ball as others watch'. Replace the letter 'a' with 'n' in the sentence.

Ex Output:
n young bnsebnll plnyer throws the bnll ns others wntch


Ex Input:
Sentence: 'busy city street with pedestrians and cars with lights all around'. Replace the letter 'r' with 'k' in the sentence.

Ex Output:
busy city stkeet with pedestkians and caks with lights all akound


Ex Input:
Sentence: 'the young boy is carrying his skateboard in the grass'. Replace the letter 'y' with 'e' in the sentence.

Ex Output:

the eoung boe is carreing his skateboard in the grass