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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 _pull_player_data(self):
 """ Pull and aggregate all player information. Pull the player's HTML stats page and parse unique properties, such as the player's height, weight, and name. Next, combine all stats for all seasons plus the player's career stats into a single object which can easily be iterated upon. Returns ------- dictionary Returns a dictionary of the player's combined stats where each key is a string of the season and the value is the season's associated stats. """

        player_info = self._retrieve_html_page()
        if not player_info:
            return
        self._parse_player_information(player_info)
        all_stats = self._combine_all_stats(player_info)
        setattr(self, '_season', list(all_stats.keys()))
        return all_stats