class_docstr: The :class:`CallbackList` class is a wrapper for a list of callbacks which acts as a single :class:`.Callback` and
  internally calls each :class:`.Callback` in the given list in turn.
  
  Args:
      callback_list (list): The list of callbacks to be wrapped. If the list contains a :class:`CallbackList`, this
          will be unwrapped.
class_docstr_tok: ["The",":","class",":","`","CallbackList","`","class","is","a","wrapper","for","a","list","of","callbacks","which","acts","as","a","single",":","class",":","`",".Callback","`","and","internally","calls","each",":","class",":","`",".Callback","`","in","the","given","list","in","turn",".","Args",":","callback_list","(","list",")",":","The","list","of","callbacks","to","be","wrapped",".","If","the","list","contains","a",":","class",":","`","CallbackList","`",",","this","will","be","unwrapped","."]
docstr: Get a dict containing all of the callback states.
  
  Returns:
      dict: A dict containing parameters and persistent buffers.
docstr_tok: ["Get","a","dict","containing","all","of","the","callback","states",".","Returns",":","dict",":","A","dict","containing","parameters","and","persistent","buffers","."]
code: def state_dict(self):
      """Get a dict containing all of the callback states.
  
      Returns:
          dict: A dict containing parameters and persistent buffers.
      """
      state_dict = {
          CallbackList.CALLBACK_STATES: [],
          CallbackList.CALLBACK_TYPES: [],
      }
  
      def to_state(callback):
          state_dict[CallbackList.CALLBACK_STATES].append(
              callback.state_dict()
          )
          state_dict[CallbackList.CALLBACK_TYPES].append(
              callback.__class__
          )
  
      self._for_list(to_state)
  
      return state_dict
  
imports: from torchbearer import Callback
label_desc: Use image node_id 2 for calling the CallbackList obj's underlying member method code with example usage: obj.state_dict() and returns: state_dict