def verify_relayable_signature(public_key, doc, signature):
sig_hash = _create_signature_hash(doc)<EOL>cipher = PKCS1_v1_5.new(RSA.importKey(public_key))<EOL>return cipher.verify(sig_hash, b64decode(signature))<EOL>
Verify the signed XML elements to have confidence that the claimed
author did actually generate this message.