def _get_candidate_names():
 global _name_sequence
 if (_name_sequence is None):
  _once_lock.acquire()
  try:
   if (_name_sequence is None):
    _name_sequence = _RandomNameSequence()
  finally:
   _once_lock.release()
 return _name_sequence

def _get_candidate_names ( ) : global _name_sequence if ( _name_sequence is None ) : _once_lock . acquire ( ) try : if ( _name_sequence is None ) : _name_sequence = _RandomNameSequence ( ) finally : _once_lock . release ( ) return _name_sequence
common setup sequence for all user-callable interfaces .