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

Example Input: Sentence: 'a pizza sitting on top of a metal pizza pan'. Replace the letter 'p' with 't' in the sentence.
Example Output: a tizza sitting on tot of a metal tizza tan

Example Input: Sentence: 'this refrigerator is covered in stickers on it'. Replace the letter 't' with 'h' in the sentence.
Example Output: hhis refrigerahor is covered in shickers on ih

Example Input: Sentence: 'a young girl sitting on a public bench holding her hands to her eyes'. Replace the letter 'b' with 'g' in the sentence.
Example Output:
a young girl sitting on a puglic gench holding her hands to her eyes