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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 load_key(self, key):
 """ Load a RSA key. Try to serialize the key before binding it to this instance. :param key: An RSA key instance """


        self._serialize(key)
        if isinstance(key, rsa.RSAPrivateKey):
            self.priv_key = key
            self.pub_key = key.public_key()
        else:
            self.pub_key = key

        return self