import json


def make_split_change_event(change_number):
    """Make a split change event."""
    return {
        'event': 'message',
        'data': json.dumps({
            'id':'TVUsxaabHs:0:0',
            'clientId':'pri:MzM0ODI1MTkxMw==',
            'timestamp': change_number-1,
            'encoding':'json',
            'channel':'MTYyMTcxOTQ4Mw==_MjA4MzczNDU1Mg==_splits',
            'data': json.dumps({
                'type': 'SPLIT_UPDATE',
                'changeNumber': change_number
            })
        })
    }