https://learn.microsoft.com/en-us/dotnet/api/system.xml.xmldictionarywriter.createmtomwriter?view=netframework-4.8.1&viewFallbackFrom=net-10.0
XmlDictionaryWriter.CreateMtomWriter Method (System.Xml) | Microsoft Learn
Creates an instance of XmlDictionaryWriter that writes XML in the Message Transmission Optimization Mechanism (MTOM) format.
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