Tests whether this definition identifies a built-in parameter or not. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 17.0.0.0 (17.0.1090.0) 
Syntax
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Remarks
 For a build-in parameter this property equals one of the BuiltInParameter enumerated values. For custom-defined parameters, such as shared, global, or family parameters the value is always BuiltInParameter.INVALID.