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How do I programatically update editType attribute on com.ptc.sis.BaseUsageLink ?
This appears to be related to Arbortext or Windchill Service Information Manager.
"Link between two Base nodes used to create Windchill Service Information Manager structures (modeled)."
I do not have this installed so I cannot assist with API. Aside from pulling class up in an IDE, I would look in its package for a helper or service class.