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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 ecdh(self, identity, pubkey):
 """Derive shared secret using ECDH from remote public key."""

        log.info('please confirm GPG decryption on %s for "%s"...',
                 self.device, identity.to_string())
        with self.device:
            return self.device.ecdh(pubkey=pubkey, identity=identity)