def test_iadd(self, evt):
        rval = event.ReturnValue(append_events=[evt])
        rval2 = event.ReturnValue(eat=True, append_events=[evt])
        rset = event.ResultSet()

        rset += rval
        rset += rval2
        rset += None
        assert rset.eat
        assert rset.append_events == [evt, evt]
def get_target_input(module, input, output):
    """A forward hook which saves the tensor - attached to its graph.
    Used if we want to explain the interim outputs of a model
    """
    try:
        del module.target_input
    except AttributeError:
        pass
    setattr(module, 'target_input', input)