code: def maskname(mask):
          
          ms = mask
          name = '%s'
          if mask & IN_ISDIR:
              ms = mask - IN_ISDIR
              name = '%s|IN_ISDIR'
          return name % EventsCodes.ALL_VALUES[ms]
docs: Returns the event name associated to mask. IN_ISDIR is appended to
          the result when appropriate. Note: only one event is returned, because
          only one event can be raised at a given time.
  
          @param mask: mask.
          @type mask: int
          @return: event name.
          @rtype: str