def _create_indice(chip):
    """Account for missing indices (Duo and PrixPowr) and create them.
    
    Even if these indices do not actually exist, we still need one for 
    relational data purposes.
    """
    if not chip['game'] == 'bn4':
        # Nothing to do here.
        return chip['indice']

    indice = chip['indice']
    if indice == '??':
        if chip['name'] == 'PrixPowr':
            indice = '39'
        if chip['name'] == 'Duo':
            indice = '40'
    return indice