input: 
  def next_state(current_state: dict, user_input: str) -> dict:
      """Given a current state of a chatbot conversation and the user's input, return the next state of the conversation.
      If the user input does not match any reply in the current state, the chatbot should not change the state and should notify the user.
      >>> next_state(state0, 'I need some advice') == state1
      True
      >>> next_state(state2, 'Why is coding so hard') == state6
      True
      >>> next_state(state1, 'Some random input') == state1
      True
      """
  
output:     if user_input in current_state:
          return current_state[user_input]
      else:
          return current_state