input: Write a function to simulate a simple chatbot that responds to "Hello" with "Hi there!" and to any other input with "I'm not sure what you mean, please try again."
  assert chatbot_response("Hello") == "Hi there!"
  assert chatbot_response("Hi") == "I'm not sure what you mean, please try again."
  assert chatbot_response("How are you?") == "I'm not sure what you mean, please try again."
output: def chatbot_response(message):
      if message == "Hello":
          return "Hi there!"
      else:
          return "I'm not sure what you mean, please try again."