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

Example Input: Sentence: 'a group of men and women sitting next to each other'. Replace the letter 'p' with 'l' in the sentence.
Example Output: a groul of men and women sitting next to each other

Example Input: Sentence: 'traffic congestion with cars and an electric tram'. Replace the letter 'a' with 'k' in the sentence.
Example Output: trkffic congestion with ckrs knd kn electric trkm

Example Input: Sentence: 'a man riding a horse attempting to wrangle a calf with a rope'. Replace the letter 'c' with 'u' in the sentence.
Example Output:
a man riding a horse attempting to wrangle a ualf with a rope