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

Ex Input:
Sentence: 'two zebras are snuggling at the zoo in their display area'. Replace the letter 'e' with 'z' in the sentence.

Ex Output:
two zzbras arz snuggling at thz zoo in thzir display arza


Ex Input:
Sentence: 'a couple of giraffe standing next to each other'. Replace the letter 't' with 'c' in the sentence.

Ex Output:
a couple of giraffe scanding nexc co each ocher


Ex Input:
Sentence: 'classic across the thames of "big ben" and parliament'. Replace the letter 'f' with 'c' in the sentence.

Ex Output:

classic across the thames oc "big ben" and parliament