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

Example Input: Sentence: 'a woman holding the arm of a life size teddy bear in a guard outfit'. Replace the letter 'g' with 'a' in the sentence.
Example Output: a woman holdina the arm of a life size teddy bear in a auard outfit

Example Input: Sentence: 'the person rides down the path atop the pink skateboard'. Replace the letter 'e' with 'c' in the sentence.
Example Output: thc pcrson ridcs down thc path atop thc pink skatcboard

Example Input: Sentence: 'a white truck is driving down the street'. Replace the letter 'h' with 'a' in the sentence.
Example Output:
a waite truck is driving down tae street