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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 is_assignee(self, login):
 """Check if the user is a possible assignee for an issue on this repository. :returns: :class:`bool` """

        if not login:
            return False
        url = self._build_url('assignees', login, base_url=self._api)
        return self._boolean(self._get(url), 204, 404)