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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_player_achievements(self, steamID, appID, language=None, format=None):
 """Request the achievements for a given app and steam id. steamID: Users steam ID appID: The app id language: The language to return the results in. None uses default. format: Return format. None defaults to json. (json, xml, vdf) """

        parameters = {'steamid' : steamID, 'appid' : appID}
        if format is not None:
            parameters['format'] = format
        if language is not None:
            parameters['l'] = language
        else:
            parameters['l'] = self.language
        url = self.create_request_url(self.interface, 'GetPlayerAchievements', 1,
            parameters)
        data = self.retrieve_request(url)
        return self.return_data(data, format=format)