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: Tom took up the sport of golf in April. Sentence2: Soon he became frustrated that his golf score was not improving. Sentence3: He decided to seek the help of a golf pro from his club. Sentence4: The pro spent numerous hours with Tom working on fundamentals. Sentence5: Tom quickly shaved ten points from his handicap.
Example Output: Club, Golf pro, Golf, Tom

Example Input: Sentence1: Gina went for a walk near her home. Sentence2: At the end of the walkway was an orange construction sign. Sentence3: Gina walked over to see what the sign said. Sentence4: The sign stated a major street would be closing for repairs. Sentence5: It would be inconvenient, but Gina hoped it would at least be quick.
Example Output: Gina

Example Input: Sentence1: Laura's cat had run away from home. Sentence2: Laura chased her cat to a tree. Sentence3: Laura's cat meowed because it was unable to get down. Sentence4: Laura called the fire department. Sentence5: A friendly firefighter was able to bring her cat out of the tree.
Example Output:
Laura, Firefighter, Cat