How to use?

As a "normal" programmer using DataBlocks, how do I make use of this class?
I would like to add custom attributes, would that be possible?

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#### Document Details

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* ID: b191c0c8-d951-2101-b495-f5b453e169ff
* Version Independent ID: 54a2867c-04f8-9a74-aa2a-5430cac6e224
* Content: [DataflowMessageHeader Struct (System.Threading.Tasks.Dataflow)](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.dataflow.dataflowmessageheader?view=netcore-2.2)
* Content Source: [xml/System.Threading.Tasks.Dataflow/DataflowMessageHeader.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Threading.Tasks.Dataflow/DataflowMessageHeader.xml)
* Product: **dotnet-api**
* GitHub Login: @rpetrusha
* Microsoft Alias: **ronpet**