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: Charles' mother advised him not to open any credit accounts. Sentence2: But, all of his friends in college were opening credit accounts. Sentence3: Charles applied for an American Express and a Visa card. Sentence4: After a few months, he couldn't pay for either card. Sentence5: Twenty years later, Charles still has a poor credit score.
Output:
His friends, Friends in college, Charles, Charles' mother