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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 sections(self):
    '''
    List of section titles from the table of contents on the page.
    '''

    if not getattr(self, '_sections', False):
      query_params = {
        'action': 'parse',
        'prop': 'sections',
      }
      query_params.update(self.__title_query_param)

      request = _wiki_request(query_params)
      self._sections = [section['line'] for section in request['parse']['sections']]

    return self._sections