def get_enz_remnant(enz):
    """Get enzyme recognition site remnant sequence"""
    if enz.ovhg > 0:
        remnant = enz.site[enz.fst3:]
        return [remnant,remnant.replace('G','A')]
    else:
        remnant = enz.site[enz.fst5:]
        return [remnant,remnant.replace('C','T')]