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

Ex Input:
Sentence: 'a small train is on the tracks by a house'. Replace the letter 'l' with 'x' in the sentence.

Ex Output:
a smaxx train is on the tracks by a house


Ex Input:
Sentence: 'a large white sign with black lettering  leaning against a metal fence'. Replace the letter 'e' with 'j' in the sentence.

Ex Output:
a largj whitj sign with black ljttjring  ljaning against a mjtal fjncj


Ex Input:
Sentence: 'wooden park bench sitting between two trees with grassy background'. Replace the letter 'i' with 'q' in the sentence.

Ex Output:

wooden park bench sqttqng between two trees wqth grassy background