Error fix for generate_self_concise_attestation

iroha-drip-general-master/drippy/host_identity.py

@@ -74,6 +74,15 @@ class HostIdentity:
     sign_key = SigningKey(unhexlify(self._priv_key))
     return hexlify(sign_key.sign(unhexlify(message)))
 
+  def generate_self_concise_attestation(self, expiration):
+    if expiration <= astm_time():
+      print("expiration timestamp has already expired.")
+      return None
+    
+    message = self._hhit  + "{:>08x}".format(convert_be_to_le(expiration))
+    sign_key = SigningKey(unhexlify(self._priv_key))
+    return hexlify(sign_key.sign(unhexlify(message)))
+
 ##############################
   ## Function for DRIP_Wrapper
 ##############################