code: def from_template_string(string, **kwargs):
      
      tmpl = _render_template(string, **kwargs)
      mail = Mail()
      mail.set_from_template_string(tmpl)
      return mail
docs: Reads the given SMTP formatted template, and creates a new Mail object
      using the information.
  
      :type  string: str
      :param string: The SMTP formatted template.
      :type  kwargs: str
      :param kwargs: Variables to replace in the template.
      :rtype:  Mail
      :return: The resulting mail.