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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 create_key(self, title, key):
 """Create a new key for the authenticated user. :param str title: (required), key title :param key: (required), actual key contents, accepts path as a string or file-like object :returns: :class:`Key <github3.users.Key>` """

        created = None

        if title and key:
            url = self._build_url('user', 'keys')
            req = self._post(url, data={'title': title, 'key': key})
            json = self._json(req, 201)
            if json:
                created = Key(json, self)
        return created