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

Ex Input:
Sentence: 'a couple of giraffe standing next to each other in a forest'. Replace the letter 'a' with 'w' in the sentence.

Ex Output:
w couple of girwffe stwnding next to ewch other in w forest


Ex Input:
Sentence: 'a dirt bike rider that is riding in the mud'. Replace the letter 'a' with 'o' in the sentence.

Ex Output:
o dirt bike rider thot is riding in the mud


Ex Input:
Sentence: 'a large specimen of zebras, or african equids'. Replace the letter 's' with 'r' in the sentence.

Ex Output:

a large rpecimen of zebrar, or african equidr