def get_reference_to_embedded_list(event):
    # -*- coding: utf-8 -*-
    """This method takes a dict of the format shown below, and returns a reference to
    the "items" list found inside it. If the incoming 'event' parameter doesn't have the
    expected format, an empty list is returned.

    Here is an example input which has the required structure. The list [1,2,3] would be
    returned with this as the incoming 'event' parameter:

        {
            "detail": {
                "requestParameters": {
                    "tagSet": {
                        "items": [ 1, 2, 3 ]
                    }
                }
            }
        }

    Parameters
    ----------
    event : dict
        The incoming dict should have the structure shown ealier with the "items" key in
        it. If it doesn't have that structure, then 'None' will be returned.

    Returns
    -------
    list
        The returned list will have the value of the nested "items" key as found in the
        incoming 'event' parameter. If that key is not found, then an empty list will be
        returned.
    """
    if not event:
        return []
    return event.get("detail",{}).get("requestParameters",{}).get("tagSet",{}).get("items",[])