In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.

Example input: Sentence1: My dog was bored. Sentence2: I was working all day so I couldn't spend time with him. Sentence3: When I finished work I decided to play with my dog. Sentence4: He was so happy to finally have some fun! Sentence5: Alas, he fell sick and died.
Example output: I (myself), Dog
Example explanation: There is only two characters in given story, i.e., I (myself) and dog.
Q: Sentence1: I used to smoke when I was younger. Sentence2: No matter the weather I never smoked inside. Sentence3: One day I was lighting a cigarette as i walked out the door. Sentence4: I looked up and saw three federal agents standing next to me. Sentence5: It turned out they were looking for the previous tenant.
A:
I (myself), Three federal agents