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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 sign(self, msg: Dict) -> Dict: """ Return a signature for the given message. """

        ser = serialize_msg_for_signing(msg, topLevelKeysToIgnore=[f.SIG.nm])
        bsig = self.naclSigner.signature(ser)
        sig = base58.b58encode(bsig).decode("utf-8")
        return sig