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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_authorizations(self, number=-1, etag=None):
 """Iterate over authorizations for the authenticated user. This will return a 404 if you are using a token for authentication. :param int number: (optional), number of authorizations to return. Default: -1 returns all available authorizations :param str etag: (optional), ETag from a previous request to the same endpoint :returns: generator of :class:`Authorization <Authorization>`\ s """

        url = self._build_url('authorizations')
        return self._iter(int(number), url, Authorization, etag=etag)