'Loads optimizer (updater) state from a file.
Parameters
fname : str
Path to input states file.'

def load_optimizer_states(self, fname):

    assert self.optimizer_initialized
    if self._update_on_kvstore:
        self._kvstore.load_optimizer_states(fname)
    else:
        self._updater.set_states(open(fname, 'rb').read())
