docs: def clean(self, critical=False):
          """Clean the logs list by deleting finished items.
  
          By default, only delete WARNING message.
          If critical = True, also delete CRITICAL message.
          """
          # Create a new clean list
          clean_events_list = []
          while self.len() > 0:
              item = self.events_list.pop()
              if item[1] < 0 or (not critical and item[2].startswith("CRITICAL")):
                  clean_events_list.insert(0, item)
          # The list is now the clean one
          self.events_list = clean_events_list
          return self.len()