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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_pages_builds(self, number=-1, etag=None):
 """Iterate over pages builds of this repository. :returns: generator of :class:`PagesBuild <github3.repos.pages.PagesBuild>` """

        url = self._build_url('pages', 'builds', base_url=self._api)
        return self._iter(int(number), url, PagesBuild, etag=etag)