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

Example Input: Sentence: 'a person scooping from a large pot of soup on the stove into a soup bowl'. Replace the letter 'a' with 'x' in the sentence.
Example Output: x person scooping from x lxrge pot of soup on the stove into x soup bowl

Example Input: Sentence: 'a man is posing in a desert, leaning on a sign with an image of a camel on it'. Replace the letter 'i' with 'r' in the sentence.
Example Output: a man rs posrng rn a desert, leanrng on a srgn wrth an rmage of a camel on rt

Example Input: Sentence: 'a group of people are walking with snow shoes on'. Replace the letter 's' with 'b' in the sentence.
Example Output:
a group of people are walking with bnow bhoeb on