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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 get_owned_games(self, steamID, include_appinfo=1, include_played_free_games=0, appids_filter=None, format=None):
 """Request a list of games owned by a given steam id. steamID: The users id include_appinfo: boolean. include_played_free_games: boolean. appids_filter: a json encoded list of app ids. format: Return format. None defaults to json. (json, xml, vdf) """

        parameters = {
                    'steamid' : steamID,
                    'include_appinfo' : include_appinfo,
                    'include_played_free_games' : include_played_free_games
                    }
        if format is not None:
            parameters['format'] = format
        if appids_filter is not None:
            parameters['appids_filter'] = appids_filter
        url = self.create_request_url(self.interface, 'GetOwnedGames', 1,
            parameters)
        data = self.retrieve_request(url)
        return self.return_data(data, format=format)