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: Frank decided to try rock climbing out as a sport. Sentence2: He practiced for a few months inside of a gym with safety gear. Sentence3: After those months he finally decided to try and climb up a mountain. Sentence4: He got his gear and drove to a nearby mountain and began climbing. Sentence5: His hard work paid off when he looked down at the world from the top.
Output:
Frank