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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 pubkey(self, identity, ecdh=False):
 """Return public key as VerifyingKey object."""

        with self.device:
            pubkey = self.device.pubkey(ecdh=ecdh, identity=identity)
        return formats.decompress_pubkey(
            pubkey=pubkey, curve_name=identity.curve_name)