input: Write a function to create a simple chatbot using Python and state diagrams. The chatbot should initialize with a starting state and allow users to navigate through different states based on their inputs. The function should return the conversation history when the chat ends.
  
  assert create_chatbot({}, [])==["Hello! How can I help you?", ">> ", "Goodbye!", "=========================", "Conversation:", "Hello! How can I help you?", ">> "]
  assert create_chatbot({'state0': {'message': 'Hello! How can I help you?', 'replies': {}}}, [])==["Hello! How can I help you?", ">> ", "I don't understand what you mean. Please try again.", "=========================", "Conversation:", "Hello! How can I help you?", ">> "]
  assert create_chatbot({'state0': {'message': 'Hello! How can I help you?', 'replies': {'I need some advice': 'state1'}}, 'state1': {'message': 'Sure, what kind of advice do you need?', 'replies': {}}}, ["Hello! How can I help you?", ">> I need some advice"])==["Hello! How can I help you?", ">> I need some advice", "Sure, what kind of advice do you need?", ">> ", "Goodbye!", "=========================", "Conversation:", "Hello! How can I help you?", ">> I need some advice", "Sure, what kind of advice do you need?", ">> "]
  assert create_chatbot({'state0': {'message': 'Hello! How can I help you?', 'replies': {'I need some advice': 'state1'}}, 'state1': {'message': 'Sure, what kind of advice do you need?', 'replies': {'Career advice': 'state3', 'Health advice': 'state4'}}, 'state3': {'message': 'It is always a good idea to research the field you are interested in and creating a plan to learn the skills that are required. Make sure to contact professionals in the field to understand their experience.', 'replies': {}}, 'state4': {'message': 'Focus on eating healthy and staying active. Make sure to consult a medical professional if you have any concerns.', 'replies': {}}}, ["Hello! How can I help you?", ">> I need some advice", "Claim", "Focus"])==["Hello! How can I help you?", ">> I need some advice", "Sure, what kind of advice do you need?", ">> Claim", "I don't understand what you mean. Please try again.", "Sure, what kind of advice do you need?", ">> Focus", "I don't understand what you mean. Please try again.", "=========================", "Conversation:", "Hello! How can I help you?", ">> I need some advice", "Sure, what kind of advice do you need?", ">> Claim", "I don't understand what you mean. Please try again.", "Sure, what kind of advice do you need?", ">> Focus", "I don't understand what you mean. Please try again."]
output: def create_chatbot(state_diagram, user_inputs):
      conversation = []
      current_state = 'state0'
      conversation.append(state_diagram[current_state]['message'])
      conversation.append(">> ")
      
      for user_input in user_inputs:
          conversation[-1] += user_input
          if user_input in state_diagram[current_state]['replies']:
              current_state = state_diagram[current_state]['replies'][user_input]
              conversation.append(state_diagram[current_state]['message'])
          else:
              conversation.append("I don't understand what you mean. Please try again.")
          conversation.append(">> ")
      
      conversation.append("Goodbye!")
      conversation.append("=========================")
      conversation.append("Conversation:")
      conversation.extend(conversation[:-3])
      return conversation