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: zone.rb
    path of file: ./repos/manageiq/app/models
    
    the code of the file until where you have to start completion: class Zone < ApplicationRecord
  validates_presence_of   :name, :description
  validates :name, :unique_within_region => true

  serialize :settings, Hash

  belongs_to :log_file_depot, :class_name => "FileDepot"
    
  def self.determine_queue_zone(options)
    if options.key?(:zone)
      options[:zone] # return specified zone including nil (aka ANY zone)
    elsif options[:role] && ServerRole.regional_role?(options[:role])
      nil # ANY zone, will be limited by role
    else
      MiqServer.my_zone
    end