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: Waiting for the next train to pull up, Harry was nervous. Sentence2: He was only a few hours away from his big interview. Sentence3: Spending the last three months sending out resumes, this was it. Sentence4: Boarding the train, he noticed something strange about the inside. Sentence5: He had hopped on the wrong color train, and would be late.
Example Output: Harry

Example Input: Sentence1: When the little boy went home, he couldn't find his mother or father. Sentence2: He looked all around. Sentence3: He called their names but no one answered. Sentence4: Eventually a neighbor heard him. Sentence5: She said his parents were at her home.
Example Output: Mother, Father, Neighbor, The little boy

Example Input: Sentence1: Eli was singing loudly to Sia's Cheap Thrills. Sentence2: Suddenly there was a banging on the door! Sentence3: The neighbors had called the cops because of the noise. Sentence4: Eli was very embarrassed because he thought no one could hear him. Sentence5: Eli started listening to his music with headphones.
Example Output:
Neighbors, Eli