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

Example Input: Sentence: 'a red stop signed has been altered to say stop hate'. Replace the letter 'e' with 't' in the sentence.
Example Output: a rtd stop signtd has bttn alttrtd to say stop hatt

Example Input: Sentence: 'a group of men and women sitting next to each other'. Replace the letter 'p' with 'l' in the sentence.
Example Output: a groul of men and women sitting next to each other

Example Input: Sentence: 'two older people wearing badges are holding an umbrella'. Replace the letter 'e' with 'p' in the sentence.
Example Output:
two oldpr ppoplp wparing badgps arp holding an umbrplla