Specify which trials to use in subsequent analysis steps.

        This function masks trials based on their class labels.

        Parameters
        ----------
        labels : list of class labels
            Marks all trials that have a label that is in the `labels` list for further processing.

        Returns
        -------
        self : Workspace
            The Workspace object.

def set_used_labels(self, labels):
        """ Specify which trials to use in subsequent analysis steps.

        This function masks trials based on their class labels.

        Parameters
        ----------
        labels : list of class labels
            Marks all trials that have a label that is in the `labels` list for further processing.

        Returns
        -------
        self : Workspace
            The Workspace object.
        """
        mask = np.zeros(self.cl_.size, dtype=bool)
        for l in labels:
            mask = np.logical_or(mask, self.cl_ == l)
        self.trial_mask_ = mask
        return self