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

Example Input: Sentence: 'a fire hydrant with a message painted on it'. Replace the letter 'n' with 'j' in the sentence.
Example Output: a fire hydrajt with a message paijted oj it

Example Input: Sentence: 'a dog standing near a potted plant outside'. Replace the letter 'a' with 'j' in the sentence.
Example Output: j dog stjnding nejr j potted pljnt outside

Example Input: Sentence: 'a brown horse standing in front of a white light tower'. Replace the letter 'i' with 'l' in the sentence.
Example Output:
a brown horse standlng ln front of a whlte llght tower