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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def start_numbered_list(self):
 """Start a numbered list."""

        self._ordered = True
        self.start_container(List, stylename='_numbered_list')
        self.set_next_paragraph_style('numbered-list-paragraph'
                                      if self._item_level <= 0
                                      else 'sublist-paragraph')