Hello - I have a question re: EKS multi-stacks setup. I created an EKS cluster with no nodes via pulumi, and want to have a separate Pulumi stack to create Managed Node Groups in that cluster. The snippet of code used:

ref = pulumi.StackReference('eks_cluster', cluster_name)
core = ref.get_output('core')

eks.ManagedNodeGroup(
    'mng',
    cluster=core,
    node_role=ec2_role,
    node_group_name=...

I get this error:

grpc._channel._InactiveRpcError: <_InactiveRpcError of RPC that terminated with:
    	status = StatusCode.UNKNOWN
    	details = "Cannot read properties of undefined (reading 'map')"
    	debug_error_string = "{"created":"@1652304221.921855000","description":"Error received from peer ipv4:127.0.0.1:49189","file":"src/core/lib/surface/call.cc","file_line":953,"grpc_message":"Cannot read properties of undefined (reading 'map')","grpc_status":2}"

Do I need to set

parent

to the cluster Output from the reference? or am I missing something?