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: David was whistling in class. Sentence2: The teacher didn't know who was making the noise. Sentence3: She didn't know who to punish. Sentence4: One of the students told the teacher after class that it was David. Sentence5: The next time David whistled, the teacher blamed David.
Example Output: One of the students, Teacher, David

Example Input: Sentence1: Jane got pregnant. Sentence2: She did was using birth control. Sentence3: The doctor said the baby could come out wrong. Sentence4: Jane wasn't ready for all that. Sentence5: She decided to get an abortion.
Example Output: Jane, Baby, Doctor

Example Input: Sentence1: Leah had a job interview tomorrow morning. Sentence2: She stayed up late updating her resume. Sentence3: She arrived at the interview 20 minutes early. Sentence4: The interviewer noted her prompt arrival time on a clipboard. Sentence5: Leah gained confidence from the compliment given by the interviewer.
Example Output:
Leah, The interviewer