code: def flush_pages(self, white_list):
          
          white_list_page_number = []
  
          for addr in white_list:
              for page_addr in range(addr[0], addr[1], self._page_size):
                  white_list_page_number.append(page_addr // self._page_size)
  
          new_page_dict = {}
  
          # cycle over all the keys ( the page number )
          for page in self._pages:
              if page in white_list_page_number:
                  # l.debug("Page " + str(page) + " not flushed!")
                  new_page_dict[page] = self._pages[page]
  
          self._pages = new_page_dict
          self._initialized = set()
docs: :param white_list: white list of page number to exclude from the flush