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

Input: Consider Input: Sentence: 'a person is riding a skateboard in a skateboard park'. Replace the letter 'a' with 'o' in the sentence.

Output: o person is riding o skoteboord in o skoteboord pork


Input: Consider Input: Sentence: 'a crowd looking at a trio of planes that are sitting idle'. Replace the letter 'a' with 'e' in the sentence.

Output: e crowd looking et e trio of plenes thet ere sitting idle


Input: Consider Input: Sentence: 'a police officer riding her horse paroling the city'. Replace the letter 'f' with 'i' in the sentence.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Output: a police oiiicer riding her horse paroling the city


