Instructions: 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: Chris, a true cowboy, was going to a local bull riding championship. Sentence2: While sitting up front, a bull with a rider rages towards him. Sentence3: It slams into the fencing, throwing its rider high into the air. Sentence4: The rider's hat goes flying and Chris manages to catch it. Sentence5: This is the most exciting bull riding event he has ever been to.
Output:
Chris