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.

Ex Input:
Sentence1: Tim had been trying to have a child with his wife for years. Sentence2: It was with great pride that he was now holding his newborn son. Sentence3: At the hospital, Tim could not help but grin. Sentence4: The nurses and doctors noticed this as well. Sentence5: Tim left the hospital, a changed man.

Ex Output:
Nurses, Tim, Doctors, Newborn son, Wife

Ex Input:
Sentence1: Simon invited his friend Joey over for a play-date. Sentence2: He was looking forward to playing Minecraft with his friend. Sentence3: Right before Joey arrived, the internet went out. Sentence4: Simon tried resetting the router, but it didn't help. Sentence5: Simon and Joey played outside until the router was back online.

Ex Output:
Simon, Joey

Ex Input:
Sentence1: Becky went to the zoo with her friend. Sentence2: They walked to the back of the zoo. Sentence3: They saw Chimpanzees at the back of the zoo. Sentence4: Becky made a funny face and danced in front of the Chimp. Sentence5: The Chimp responded by defecating and tossing feces at Becky.

Ex Output:
Friends, Becky's friend, Becky, Chimpanzees