code: def parse_authentication_request(self, request_body, http_headers=None):
          # type: (str, Optional[Mapping[str, str]]) -> oic.oic.message.AuthorizationRequest
          
  
          auth_req = AuthorizationRequest().deserialize(request_body)
  
          for validator in self.authentication_request_validators:
              validator(auth_req)
  
          logger.debug('parsed authentication_request: %s', auth_req)
          return auth_req
docs: Parses and verifies an authentication request.
  
          :param request_body: urlencoded authentication request
          :param http_headers: http headers