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: 'an airplane moves through the skies above a snowy mountain range'. Replace the letter 'l' with 's' in the sentence.

Ex Output:
an airpsane moves through the skies above a snowy mountain range


Ex Input:
Sentence: 'a street light is near a large building'. Replace the letter 'n' with 'c' in the sentence.

Ex Output:

a street light is cear a large buildicg