.NET COM events using IDispatch are not handled

In C#, as a guideline, events are exposed by an `IDispatch` interface for late-binding only, by using the attribute `[InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]`.

It seems like there's no way to sink those events, a code like follows:
```
class IEvents():
def IEvents_OnResult(self, this, result):
print(f"Event! {result}")

from comtypes.client import GetEvents
sink = IEvents()
connection = GetEvents(obj, sink)
```
will cause the error `_ctypes.COMError: (-2147467263, 'Not implemented', ('The method or operation is not implemented.', 'mscorlib', None, 0, None))`

Is there a way to handle this use case?

Thanks