def clear_mappers():
 mapperlib._CONFIGURE_MUTEX.acquire()
 try:
  while _mapper_registry:
   try:
    (mapper, b) = _mapper_registry.popitem()
    mapper.dispose()
   except KeyError:
    pass
 finally:
  mapperlib._CONFIGURE_MUTEX.release()

def clear_mappers ( ) : mapperlib . _CONFIGURE_MUTEX . acquire ( ) try : while _mapper_registry : try : ( mapper , b ) = _mapper_registry . popitem ( ) mapper . dispose ( ) except KeyError : pass finally : mapperlib . _CONFIGURE_MUTEX . release ( )
remove all mappers from all classes .