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: Consider Input: Sentence1: Jeff is carrying is walking across the street. Sentence2: A car comes and hits him. Sentence3: He goes soaring through the air. Sentence4: Jeff lands on his feet. Sentence5: Jeff is uninjured and finishes walking across the street.

Output: Jeff

Input: Consider Input: Sentence1: Bret went mountain climbing in Alaska. Sentence2: He was near the summit of the mountain when a storm struck. Sentence3: Bret had to build a snow cave to keep warm. Sentence4: Bret survived the storm that lasted two days. Sentence5: Bret was glad that he knew mountain survival techniques.

Output: Bret

Input: Consider Input: Sentence1: Jake wanted to join little league. Sentence2: He had asthma and his parents were worried. Sentence3: He convinced them to let him. Sentence4: He had a lot of fun. Sentence5: His parents decided to trust him more.
Output: His parents, Jake