def _sorted_keys(self, keys):
        sorted_keys = []
        if ('epoch' in keys) and ('epoch' not in self.keys_ignored_):
            sorted_keys.append('epoch')
        for key in sorted(keys):
            if not (
                    (key in ('epoch', 'dur')) or
                    (key in self.keys_ignored_) or
                    key.endswith('_best') or
                    key.startswith('event_')
            ):
                sorted_keys.append(key)
        for key in sorted(keys):
            if key.startswith('event_') and (key not in self.keys_ignored_):
                sorted_keys.append(key)
        if ('dur' in keys) and ('dur' not in self.keys_ignored_):
            sorted_keys.append('dur')
        return sorted_keys