public sealed class UnitIdentifier 

await QueuedTask.Run(() =>
{
  using (UnitIdentifierManager unitIdentifierManager = utilityNetwork.GetUnitIdentifierManager())
  {
    var networkSource = utilityNetwork.GetDefinition().GetNetworkSource("TelecomDevice");

    // Container to query.
    UnitIdentifier containerUnitId = new UnitIdentifier(networkSource, globalID);

    // Query the unit identifiers in the container
    IReadOnlyList<UnitQueryResult> unitQueryResults = unitIdentifierManager.Query(new List<UnitIdentifier> { containerUnitId });

    // Iterate through the query results
    foreach (UnitQueryResult unitQueryResult in unitQueryResults)
    {
      UnitIdentifier unitIdentifier = unitQueryResult.Container;
      IReadOnlyList<UnitRange> unitsInAContainer = unitQueryResult.UnitRanges;

      // Iterate through the unit ranges (contents) in the container
      foreach (UnitRange unitRange in unitsInAContainer)
      {
        UnitIdentifier contentUnitId = unitRange.Content;
        bool isContentGap = unitRange.IsGap; // True if the content is a gap (empty space reserved for installing a larger piece of equipment).
        short? firstUnit = unitRange.FirstUnit;
        short? lastUnit = unitRange.LastUnit;
      }
    }
  }

});

await QueuedTask.Run(() =>
{
  using (UnitIdentifierManager unitIdentifierManager = utilityNetwork.GetUnitIdentifierManager())
  {
    var networkSource = utilityNetwork.GetDefinition().GetNetworkSource("TelecomDevice");
    UnitIdentifier containerUnitIdentifier = new UnitIdentifier(networkSource, globalID);

    // Reserve a gap in the container for units 2 through 5.
    unitIdentifierManager.ReserveUnitIDs(containerUnitIdentifier, 2, 5);
  }
});