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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def iter_events(self, number=-1):
 """Iterate over events associated with this issue only. :param int number: (optional), number of events to return. Default: -1 returns all events available. :returns: generator of :class:`IssueEvent <github3.issues.event.IssueEvent>`\ s """

        url = self._build_url('events', base_url=self._api)
        return self._iter(int(number), url, IssueEvent)