'Close all the handles used by this class.'

def close_all_handles(self):

    if (hasattr(self, 'namedpipe') and self.namedpipe):
        ovs_winutils.close_handle(self.namedpipe)
    if (hasattr(self, '_read') and self._read.hEvent):
        ovs_winutils.close_handle(self._read.hEvent)
    if (hasattr(self, '_npipe_file') and self._npipe_file):
        ovs_winutils.close_handle(self._npipe_file)
