old_contents: class Action(object):
      def __init__(self, type, body, bot, keep_session):
          if (type not in ['inquiry','message'] or
              type(keep_session) is not type(True) ):
              raise ValueError(
                  '__init__() is initialised by invalid attributes')
          self.type = type
          self.body = body
          self.bot = bot
          self.keep_session = keep_session
  
new_contents: class Action(object):
      def __init__(self, type, body, bot, keep_context):
          if (type not in ['inquiry','message'] or
              type(keep_context) is not type(True) ):
              raise ValueError(
                  '__init__() is initialised by invalid attributes')
          self.type = type
          self.body = body
          self.bot = bot
          self.keep_context = keep_context
  
subject: Rename the keep_session attr to reset_contexts