You will be given a definition of a task first, then some input of the task.
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.

Sentence1: Charles learned to be creative from his grandmother. Sentence2: One thanksgiving, she asked him to cut up a watermelon. Sentence3: Charles cut up a bunch of chunks and put them in Tupperware. Sentence4: His grandmother told him to be more creative. Sentence5: Then she carved a basket out of a watermelon and put the chunks in.
Output:
Grandmother, Charles