code: def compile(self, name, folder=None, data=None):
          
          template_name = name.replace(os.sep, "")
          if folder is None:
              folder = ""
          full_name = os.path.join(
              folder.strip(os.sep), template_name)
          if data is None:
              data = {}
          try:
              self.templates[template_name] = \
                  self.jinja.get_template(full_name).render(data)
          except TemplateNotFound as template_error:
              if current_app.config['DEBUG']:
                  raise template_error
docs: renders template_name + self.extension file with data using jinja