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

Ex Input:
Sentence: 'a man is standing with this luggage next to a railroad track'. Replace the letter 'g' with 'l' in the sentence.

Ex Output:
a man is standinl with this lullale next to a railroad track

Ex Input:
Sentence: 'an elephant in chains converses with a smaller elephant who is not wearing chains'. Replace the letter 'i' with 'm' in the sentence.

Ex Output:
an elephant mn chamns converses wmth a smaller elephant who ms not wearmng chamns

Ex Input:
Sentence: 'a man riding a skateboard down a street past a building'. Replace the letter 'e' with 'b' in the sentence.

Ex Output:
a man riding a skatbboard down a strbbt past a building