Perform an ``allocateIds`` request.

        :type project_id: str
        :param project_id: The project to connect to. This is
                           usually your project name in the cloud console.

        :type keys: List[.entity_pb2.Key]
        :param keys: The keys for which the backend should allocate IDs.

        :rtype: :class:`.datastore_pb2.AllocateIdsResponse`
        :returns: The returned protobuf response object.

def allocate_ids(self, project_id, keys):
        """Perform an ``allocateIds`` request.

        :type project_id: str
        :param project_id: The project to connect to. This is
                           usually your project name in the cloud console.

        :type keys: List[.entity_pb2.Key]
        :param keys: The keys for which the backend should allocate IDs.

        :rtype: :class:`.datastore_pb2.AllocateIdsResponse`
        :returns: The returned protobuf response object.
        """
        request_pb = _datastore_pb2.AllocateIdsRequest(keys=keys)
        return _rpc(
            self.client._http,
            project_id,
            "allocateIds",
            self.client._base_url,
            request_pb,
            _datastore_pb2.AllocateIdsResponse,
        )