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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 encrypt(self, s, mac_bytes=10):
 """ Encrypt `s' for this pubkey. """

        if isinstance(s, six.text_type):
            raise ValueError(
                "Encode `s` to a bytestring yourself to" +
                " prevent problems with different default encodings")
        out = BytesIO()
        with self.encrypt_to(out, mac_bytes) as f:
            f.write(s)
        return out.getvalue()