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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 DecryptMessage(self, encrypted_response):
 """Decrypt the serialized, encrypted string. Args: encrypted_response: A serialized and encrypted string. Returns: a Packed_Message_List rdfvalue """

    try:
      response_comms = rdf_flows.ClientCommunication.FromSerializedString(
          encrypted_response)
      return self.DecodeMessages(response_comms)
    except (rdfvalue.DecodeError, type_info.TypeValueError, ValueError,
            AttributeError) as e:
      raise DecodingError("Error while decrypting messages: %s" % e)