def zeros_only(preds, labels):
    """
    Return only those samples having a label=0
    """
    out_preds  = []
    out_labels = []
    for i, label in enumerate(labels):
        if label == 0:
            out_labels.append(label)
            out_preds.append( preds[i] )
            
    return out_preds, out_labels