Moving old function into _non_upstream_helpers.

It's been moved into core.

gcloud_bigtable/_non_upstream_helpers.py

@@ -340,3 +340,27 @@ def _pb_timestamp_to_datetime(timestamp):
             microseconds=(timestamp.nanos / 1000.0),
         )
     )
+
+
+def _get_pb_property_value(message_pb, property_name):
+    """Return a message field value.
+
+    :type message_pb: :class:`google.protobuf.message.Message`
+    :param message_pb: The message to check for ``property_name``.
+
+    :type property_name: str
+    :param property_name: The property value to check against.
+
+    :rtype: object
+    :returns: The value of ``property_name`` set on ``message_pb``.
+    :raises: :class:`ValueError <exceptions.ValueError>` if the result returned
+             from the ``message_pb`` does not contain the ``property_name``
+             value.
+    """
+    # Make sure `property_name` is set on the response.
+    # NOTE: As of proto3, HasField() only works for message fields, not for
+    #       singular (non-message) fields.
+    all_fields = set([field.name for field in message_pb._fields])
+    if property_name not in all_fields:
+        raise ValueError('Message does not contain %s.' % (property_name,))
+    return getattr(message_pb, property_name)

gcloud_bigtable/cluster.py

@@ -24,6 +24,7 @@
     bigtable_cluster_service_messages_pb2 as messages_pb2)
 from gcloud_bigtable._generated import (
     bigtable_table_service_messages_pb2 as table_messages_pb2)
+from gcloud_bigtable._non_upstream_helpers import _get_pb_property_value
 from gcloud_bigtable._non_upstream_helpers import _pb_timestamp_to_datetime
 from gcloud_bigtable.table import Table
 
@@ -47,30 +48,6 @@
 }
 
 
-def _get_pb_property_value(message_pb, property_name):
-    """Return a message field value.
-
-    :type message_pb: :class:`google.protobuf.message.Message`
-    :param message_pb: The message to check for ``property_name``.
-
-    :type property_name: str
-    :param property_name: The property value to check against.
-
-    :rtype: object
-    :returns: The value of ``property_name`` set on ``message_pb``.
-    :raises: :class:`ValueError <exceptions.ValueError>` if the result returned
-             from the ``message_pb`` does not contain the ``property_name``
-             value.
-    """
-    # Make sure `property_name` is set on the response.
-    # NOTE: As of proto3, HasField() only works for message fields, not for
-    #       singular (non-message) fields.
-    all_fields = set([field.name for field in message_pb._fields])
-    if property_name not in all_fields:
-        raise ValueError('Message does not contain %s.' % (property_name,))
-    return getattr(message_pb, property_name)
-
-
 def _prepare_create_request(cluster):
     """Creates a protobuf request for a CreateCluster request.