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

Ex Input:
Sentence: 'several older electronics, including cellular phones and a palm pilot with a  broken screen next to each other in white box enclosure'. Replace the letter 'u' with 't' in the sentence.

Ex Output:
several older electronics, incltding celltlar phones and a palm pilot with a  broken screen next to each other in white box enclostre


Ex Input:
Sentence: 'a photo of a river with a train bridge across it'. Replace the letter 'r' with 'f' in the sentence.

Ex Output:
a photo of a fivef with a tfain bfidge acfoss it


Ex Input:
Sentence: 'many small boats on a water at a market'. Replace the letter 'a' with 's' in the sentence.

Ex Output:

msny smsll bosts on s wster st s msrket