def METHOD_NAME(self):
    """Runs a validation test.
    This checks that a samples group exist, and that pickeled data can
    be loaded.
    Returns
    -------
    bool :
        Whether or not the file is valid as a checkpoint file.
    """
    try:
        if 'sampler_info/saved_state' in self:
            load_state(self, path='sampler_info/saved_state')
        checkpoint_valid = True
    except KeyError:
        checkpoint_valid = False
    return checkpoint_valid