code: def pages(self):
          
          # Start with a page object for unknown entries if the HAR data has
          # any entries with no page ID
          pages = []
          if any('pageref' not in entry for entry in self.har_data['entries']):
              pages.append(HarPage('unknown', har_parser=self))
          for har_page in self.har_data['pages']:
              page = HarPage(har_page['id'], har_parser=self)
              pages.append(page)
  
          return pages
docs: This is a list of HarPage objects, each of which represents a page
          from the HAR file.