Definition: 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.
Input: Sentence1: Sheri was wondering why you can sometimes see the moon in daylight. Sentence2: So, not having a computer, Sheri got in her car and drove to a library. Sentence3: Sheri arrived at the library and went inside. Sentence4: She went to the astronomy section and found a book on the moon. Sentence5: Sheri read the book, and now knows why the moon shines in the daylight.
Output:
Shen, Sheri