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

Example Input: Sentence: 'a man standing in the water flying a kite'. Replace the letter 'w' with 's' in the sentence.
Example Output: a man standing in the sater flying a kite

Example Input: Sentence: 'a woman sitting along the body of water looking at her cell phone'. Replace the letter 'e' with 'b' in the sentence.
Example Output: a woman sitting along thb body of watbr looking at hbr cbll phonb

Example Input: Sentence: 'a skateboarder does a trick in a crowded skatepark covered in graffiti'. Replace the letter 'f' with 'b' in the sentence.
Example Output:
a skateboarder does a trick in a crowded skatepark covered in grabbiti