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

Example Input: Sentence: 'a couple of giraffe standing next to each other near  a fence'. Replace the letter 'f' with 'j' in the sentence.
Example Output: a couple oj girajje standing next to each other near  a jence

Example Input: Sentence: 'a back pack and lap top sit on the kitchen counter'. Replace the letter 't' with 'k' in the sentence.
Example Output: a back pack and lap kop sik on khe kikchen counker

Example Input: Sentence: 'a yellow bedroom with with a bedspread that is half and half'. Replace the letter 'h' with 'j' in the sentence.
Example Output:
a yellow bedroom witj witj a bedspread tjat is jalf and jalf