In 3.3 iterparse accepts a tuple in events (the C accelerator enforces this).
This limitation was lifted in Python 3.4
Parses an XML section into an element tree incrementally, and reports what's
going on to the user. *source* is a filename or :term:`file object`
- containing XML data. *events* is a list of events to report back. The
+ containing XML data. *events* is a tuple of events to report back. The
supported events are the strings ``"start"``, ``"end"``, ``"start-ns"``
and ``"end-ns"`` (the "ns" events are used to get detailed namespace
information). If *events* is omitted, only ``"end"`` events are reported.