Get generic instance generic type using reflection

Given:

Type T = typeof(List<string>);

Requirement:

typeof(List<>) == SomeFunction(T)

Many times when I'm reflecting over a type and want to find all properties that return lists of some type...I need the "SomeFunction" shown above. I've searched and searched, but cannot figure 开发者_JAVA百科out how to get List<> from List<string>. I can use T.GetGenericArguments(), but that only returns string so that doesn't help at all.

typeof(List<string>).GetGenericTypeDefinition() == typeof(List<>)