You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: soa.rb
    path of file: ./repos/GloboDNS/app/models
    
    the code of the file until where you have to start completion: # Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of th
    
  def update_convenience_accessors
    return if self.content.blank? || ACCESSIBLE_SOA_FIELDS.select{ |field| send(field).blank? }.empty?

    soa_fields = self.content.split(/\s+/)
    raise Exception.new("Invalid SOA Record content attribute: #{self.content}") unless soa_fields.size == SOA_FIELDS.size

    soa_fields.each_with_index do |field_value, index|
      field_name  = SOA_FIELDS[index]
      field_value = field_value.try(:to_i) if field_name == 'serial'
      instance_variable_set("@#{field_name}", field_value)
      instance_variable_set("@#{field_name}_was", field_value)
    end
    # update_serial if @serial.nil? || @serial.zero?
  end