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: Cecil was mowing his lawn. Sentence2: He discovered a huge mound of ants in the corner of his lawn. Sentence3: Cecil went to the store and bought ant poison. Sentence4: He proceeded to poison the ants. Sentence5: The ants were gone within a few days.
Output:
Cecil, Ants