since
- Python 3 is ok from 3.7 onwards
- support for Python 3.6 was just dropped
- we do not actually know the minor version of the analysed code
(only of the extractor)
We were not supporting `except` statements handling multiple exception
types (specified as a tuple) correctly, instead just returning the
tuple itself as the "type" (which makes little sense).
To fix this, we explicitly extract the elements of this node, in the
case where it _is_ a tuple.
This is a change that can potentially affect many queries (as `getType`
is used in quite a few places), so some care should be taken to
ensure that this does not adversely affect performance.