def enable_cdc(client):
    """Utility method to enable Change Data Capture for Contact change events in an org.

    Args:
        client (:py:class:`simple_salesforce.Salesforce`): Salesforce client

    Returns:
        (:obj:`str`) Event channel Id
    """
    payload = {
        "FullName": "ChangeEvents_ContactChangeEvent",
        "Metadata": {
            "eventChannel": "ChangeEvents",
            "selectedEntity": "ContactChangeEvent"
        }
    }
    result = client.restful('tooling/sobjects/PlatformEventChannelMember', method='POST', json=payload)
    assert True == result['success']
    return result['id']