Found a problem with duplication in annotations index. It leads to https://youtrack.jetbrains.com/issue/RIDER-82353/Math.Tanh-is-annotated-as-pure-twice problem because [Pure] attribute is duplicated. 
Found a problem with duplication in annotations index. It leads to https://youtrack.jetbrains.com/issue/RIDER-82353/Math.Tanh-is-annotated-as-pure-twice problem because [Pure] attribute is duplicated.
