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

Example Input: Sentence: 'a child holding a tv remote like a phone'. Replace the letter 'i' with 'b' in the sentence.
Example Output: a chbld holdbng a tv remote lbke a phone

Example Input: Sentence: 'children trying little hamburgers from a tray at school'. Replace the letter 'y' with 'l' in the sentence.
Example Output: children trling little hamburgers from a tral at school

Example Input: Sentence: 'the sky is full of colorful kites in varying sizes'. Replace the letter 'l' with 'r' in the sentence.
Example Output:
the sky is furr of cororfur kites in varying sizes