code: def get_auth_server(domain, allow_http=False):
      
      st = get_stellar_toml(domain, allow_http)
      if not st:
          return None
      return st.get('AUTH_SERVER')
docs: Retrieve the AUTH_SERVER config from a domain's stellar.toml.
  
      :param str domain: The domain the .toml file is hosted at.
      :param bool allow_http: Specifies whether the request should go over plain
          HTTP vs HTTPS. Note it is recommend that you *always* use HTTPS.
      :return str: The AUTH_SERVER url.