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: Timmy and his friend Jason loved riding bikes. Sentence2: They would always zoom around them in the neighborhood. Sentence3: They decided to have a race to see who was fastest. Sentence4: Timmy and Jason both lined up their bikes and sped off. Sentence5: Jason came across the line first.
Output:
Jason, Timmy