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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_contributors(self, anon=False, number=-1, etag=None):
 """Iterate over the contributors to this repository. :param bool anon: (optional), True lists anonymous contributors as well :param int number: (optional), number of contributors to return. Default: -1 returns all contributors :param str etag: (optional), ETag from a previous request to the same endpoint :returns: generator of :class:`User <github3.users.User>`\ s """

        url = self._build_url('contributors', base_url=self._api)
        params = {}
        if anon:
            params = {'anon': True}
        return self._iter(int(number), url, User, params, etag)