def METHOD_NAME(instance, basedn):
    """Create the base domain object"""
    domain = Domain(instance, dn=basedn)
    # Explode the dn to get the first bit.
    avas = dn.str2dn(basedn)
    dc_ava = avas[0][0][1]
    domain.create(properties={
        # I think in python 2 this forces unicode return ...
        'dc': dc_ava,
        'description': basedn,
    })
    # ACI can be added later according to your needs
    return domain