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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 on_after_transform_template(self, template):
 """ Hook method that gets called after the template is processed Go through all the stored applications and make sure they're all ACTIVE. :param dict template: Dictionary of the SAM template :return: Nothing """

        if self._wait_for_template_active_status and not self._validate_only:
            start_time = time()
            while (time() - start_time) < self.TEMPLATE_WAIT_TIMEOUT_SECONDS:
                temp = self._in_progress_templates
                self._in_progress_templates = []

                # Check each resource to make sure it's active
                for application_id, template_id in temp:
                    get_cfn_template = (lambda application_id, template_id:
                                        self._sar_client.get_cloud_formation_template(
                                            ApplicationId=self._sanitize_sar_str_param(application_id),
                                            TemplateId=self._sanitize_sar_str_param(template_id)))
                    response = self._sar_service_call(get_cfn_template, application_id, application_id, template_id)
                    self._handle_get_cfn_template_response(response, application_id, template_id)

                # Don't sleep if there are no more templates with PREPARING status
                if len(self._in_progress_templates) == 0:
                    break

                # Sleep a little so we don't spam service calls
                sleep(self.SLEEP_TIME_SECONDS)

            # Not all templates reached active status
            if len(self._in_progress_templates) != 0:
                application_ids = [items[0] for items in self._in_progress_templates]
                raise InvalidResourceException(application_ids, "Timed out waiting for nested stack templates "
                                                                "to reach ACTIVE status.")