With boto route53, zones can only be matched by name
    or iterated over in a list.  Since the name will be the
    same for public and private zones in a split DNS situation,
    iterate over the list and match the zone name and public/private
    status.

def _get_split_zone(zone, _conn, private_zone):
    '''
    With boto route53, zones can only be matched by name
    or iterated over in a list.  Since the name will be the
    same for public and private zones in a split DNS situation,
    iterate over the list and match the zone name and public/private
    status.
    '''
    for _zone in _conn.get_zones():
        if _zone.name == zone:
            _private_zone = True if _zone.config['PrivateZone'].lower() == 'true' else False
            if _private_zone == private_zone:
                return _zone
    return False