def expand_onPremisesExtensionAttributes(entry):
    """
    entry - a dictionary that must have the "onPremisesExtensionAttributes" key defined

    This transformer takes a dictionary, and returns the same dictionary, but with the
    "onPremisesExtensionAttributes" value expanded into it's own key: value pair.
    This value must initially be a JSON.
    """
    for key, value in entry.get("onPremisesExtensionAttributes", {}).items():
        entry[key] = value
    entry.pop("onPremisesExtensionAttributes", None)
    return entry