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

Ex Input:
Sentence: 'two men and a dog are standing beside a building'. Replace the letter 'b' with 'y' in the sentence.

Ex Output:
two men and a dog are standing yeside a yuilding


Ex Input:
Sentence: 'a woman is standing on a street curb'. Replace the letter 'a' with 't' in the sentence.

Ex Output:
t womtn is sttnding on t street curb


Ex Input:
Sentence: 'a herd of long horn sheep standing in a field'. Replace the letter 'f' with 'q' in the sentence.

Ex Output:

a herd oq long horn sheep standing in a qield