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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 xdr(self):
 """Generate base64 encoded XDR PublicKey object. Return a base64 encoded PublicKey XDR object, for sending over the wire when interacting with stellar. :return: The base64 encoded PublicKey XDR structure. """

        kp = Xdr.StellarXDRPacker()
        kp.pack_PublicKey(self.account_xdr_object())
        return base64.b64encode(kp.get_buffer())