def METHOD_NAME(obj: Serializable, field: Field, value):
    if value is _NoFieldValue:
        return
    if type(value) is Placeholder:
        if field.on_deserialize is not None:
            value.callbacks.append(
                lambda v: field.set(obj, field.on_deserialize(v))
            )
        else:
            value.callbacks.append(lambda v: field.set(obj, v))
    else:
        if field.on_deserialize is not None:
            field.set(obj, field.on_deserialize(value))
        else:
            field.set(obj, value)