def etag_response_processor(page, request, response):
 etag = page.etag(request)
 if (etag is not None):
  response[u'ETag'] = ((u'"' + etag) + u'"')

def etag_response_processor ( page , request , response ) : etag = page . etag ( request ) if ( etag is not None ) : response [ u'ETag' ] = ( ( u'"' + etag ) + u'"' )
response processor to set an etag header on outgoing responses .