def __iadd__(self, other):
        self.extend(list(other))
        return self
If run inside an Eliot context, the result of C{preserve_context} is
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/contrib/gis/geos/mutable_list.py/ListMixin.__iadd__--crossover with--dataset/ETHPy150Open ClusterHQ/eliot/eliot/tests/test_action.py/PreserveContextTests.test_with_context_calls_underlying