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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_comments(self, number=-1):
 """Iterate over the comments on this issue. :param int number: (optional), number of comments to iterate over :returns: iterator of :class:`IssueComment <github3.issues.comment.IssueComment>`\ s """

        url = self._build_url('comments', base_url=self._api)
        return self._iter(int(number), url, IssueComment)