code: def _template(self, blueprint):
          
          if self.bucket_name:
              return Template(url=self.s3_stack_push(blueprint))
          else:
              return Template(body=blueprint.rendered)
docs: Generates a suitable template based on whether or not an S3 bucket
          is set.
  
          If an S3 bucket is set, then the template will be uploaded to S3 first,
          and CreateStack/UpdateStack operations will use the uploaded template.
          If not bucket is set, then the template will be inlined.