def METHOD_NAME(self, validated_data):
    if "name" not in validated_data or "owner" not in validated_data:
        raise InvalidGeoAppException("No valid data: 'name' and 'owner' are mandatory fields!")
    if self.Meta.model.objects.filter(name=validated_data["name"]).count():
        raise DuplicateGeoAppException("A GeoApp with the same 'name' already exists!")
    self.extra_update_checks(validated_data)