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: Tim had issues with his stomach. Sentence2: He kept having to use the restroom. Sentence3: Unfortunately he had to be at work soon. Sentence4: Once there he kept going to the bathroom. Sentence5: He got in trouble with his boss over it.
Output:
Tim, Tim's boss