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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_config_data(self, request, obj, name):
 """ Method that retrieves a configuration option for a specific AppHookConfig instance :param request: the request object :param obj: the model instance :param name: name of the config option as defined in the config form :return value: config value or None if no app config is found """

        return_value = None
        config = None
        if obj:
            try:
                config = getattr(obj, self.app_config_attribute, False)
            except ObjectDoesNotExist:  # pragma: no cover
                pass
        if not config and self.app_config_attribute in request.GET:
            config_model = get_apphook_model(self.model, self.app_config_attribute)
            try:
                config = config_model.objects.get(pk=request.GET[self.app_config_attribute])
            except config_model.DoesNotExist:  # pragma: no cover
                pass
        if config:
            return_value = getattr(config, name)
        return return_value