docs: def get_request_uri_parameters(self, as_dict=False):
      """ Return the URI parameters from a request passed to the 'validate' method
  
      The query parameters returned by this method **MUST** be included in the
      ``action=""`` URI of the authorization form presented to the user. This
      carries the original authorization request parameters across the request to
      show the form to the request that submits the form.
  
      :param as_dict: default ``False``. If ``True``, returns the parameters as a
          dictionary. If ``False``, returns the parameters as a URI-encoded
          string.
      """
      if not self.request:
        raise ValueError('request must have been passed to the "validate" method')
  
      return (dict if as_dict else urlencode)(self.request.REQUEST.items())