Datastore query raises a ValueError for inequality(non-equality to be correct) operators on __key__ property.
https://github.com/GoogleCloudPlatform/gcloud-python/blob/3e86aaed3c7e192a17d9b790f90a41cc2b7baa6a/gcloud/datastore/query.py#L223

According to Google Cloud Datastore documentation inquality operators on __key__ property are supported, and should not raise exception.
https://cloud.google.com/datastore/docs/concepts/queries#Datastore_Key_filters

It is a critical part of our data-model.