with out variable

zabbix_sync.rb

# ...
  def read_config_file
    puts 'file exists' if File.exists?('/usr/local/etc/zabbix_sync.conf')
    if File.exists?(config_file_name)
      binding.pry
      config_file = YAML.load(File.read config_file_name)
    else
    end
    if @config_file['blacklist'].class == Array
      blacklist = @config_file['blacklist']
    end
  end
# ...