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

Ex Input:
Sentence: 'the door of the refrigerator has many magnets and small pictures on it'. Replace the letter 's' with 'z' in the sentence.

Ex Output:
the door of the refrigerator haz many magnetz and zmall picturez on it

Ex Input:
Sentence: 'a couple of giraffe standing next to each other'. Replace the letter 't' with 'c' in the sentence.

Ex Output:
a couple of giraffe scanding nexc co each ocher

Ex Input:
Sentence: 'a person on a snowboard in the snow'. Replace the letter 'h' with 'r' in the sentence.

Ex Output:
a person on a snowboard in tre snow