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

Example Input: Sentence: 'an older man wearing a suit and tie'. Replace the letter 'i' with 't' in the sentence.
Example Output: an older man weartng a sutt and tte

Example Input: Sentence: 'a hand held game or older cell phone'. Replace the letter 'o' with 'c' in the sentence.
Example Output: a hand held game cr clder cell phcne

Example Input: Sentence: 'a lady at boston harbor with her phone and a black dog'. Replace the letter 'h' with 'i' in the sentence.
Example Output:
a lady at boston iarbor witi ier pione and a black dog