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: Mila wanted a pet. Sentence2: She went to the pet store to look for one. Sentence3: At the pet store Mila saw a puppy. Sentence4: Mila loved the puppy and took it home. Sentence5: Mila was happy she found her new pet.
Output:
New pet, Puppy, Mila