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

Example Input: Sentence: 'a man sitting in a chair with a laptop in his lap'. Replace the letter 'p' with 'v' in the sentence.
Example Output: a man sitting in a chair with a lavtov in his lav

Example Input: Sentence: 'three men playing in a men's doubles tennis match'. Replace the letter 'e' with 'l' in the sentence.
Example Output: thrll mln playing in a mln's doublls tlnnis match

Example Input: Sentence: 'a traffic light hanging over a city street'. Replace the letter 'i' with 'c' in the sentence.
Example Output:
a traffcc lcght hangcng over a ccty street