[NEST Users] Creating a new NodeCollection from Mask or by global_ids

Dear Nest Team, working with Python 3.8 and Nest 3.2 my goal is, after creating a spatial NodeCollection "neurons", to create a new NodeCollection containing a selection of the node from "neurons". To achieve this I tried two different approaches: 1. Create a Mask object and use nest.SelectNodesByMask() nodes_in_mask = nest.SelectNodesByMask(neurons, ctr_position, mask_obj) 2. Transform the NodeCollection into a list of node ids, pick 3 random ids, and create a new NodeCollection containing those 3 Nodes neurons_list = neurons.tolist() for x in range(0, 3): center = random.choice(neurons_list) node_ids.append(center) node_ids.sort() new_collection = nest.NodeCollection(node_ids) But with both approaches I get the same problems that some Information (of the positions) seems to go missing. This shows in different ways. First the new NodeCollections are no longer spatial (nodes_in_mask.spatial and new_collection.spatial return none). Second trying to get the node Positions results in an Error: nest.GetPosition(nodes_in_mask) -> Error #1 nest.lib.hl_api_exceptions.LayerExpected: LayerExpected in SLI function GetPosition_g: And last, trying to Plot the Layer also results in an Error: fig = nest.PlotLayer(nodes_in_mask) -> Error #2 TypeError: 'NoneType' object is not subscriptable I attached a .txt file containing py code showing the problems. Why do those Problems occur and what can I do to solve them? Is there a way to create an empty NodeCollection s.t. I can add the wished nodes one by one? What exactly does the metadata of a Nodecollection represent? Is there a way to set it manually for example to spatial? Thank you in advance for your Answers, Miriam