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

Ex Input:
Sentence: 'a man with a backpack on a motorcycle'. Replace the letter 't' with 'd' in the sentence.

Ex Output:
a man widh a backpack on a modorcycle


Ex Input:
Sentence: 'a herd of zebra stand together and eat grass'. Replace the letter 'n' with 'r' in the sentence.

Ex Output:
a herd of zebra stard together ard eat grass


Ex Input:
Sentence: 'an elephant's front legs are in the water and back legs are out of the water'. Replace the letter 'b' with 'r' in the sentence.

Ex Output:

an elephant's front legs are in the water and rack legs are out of the water