<= and >= operators do not work in ruby : to check if the installer is installed or not 
installer status |grep Version| cut -c12-13
the ouput says installer not found
but incase its installed it would say 11 or 10 (any numeric)
if the output is <=10 || >=11 then 
say not installed and proceed with the installation
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in the library , its given 
def get_installer_linux_version
    begin
       cmd = Mixlib::ShellOut.new('installer status |grep Version| cut -c12-13')
       cmd.run_command
     rescue Errno::ENOENT => e
       return '0.0'
    end
    return 'Version 10' if cmd.stdout.include? '10'  
    return 'Version 11' if cmd.stdout.include? '11'
  end 
===============
in the install recipe 
if get_installer_linux_version.to_i <= 10 || get_installer_linux_version.to_i >= 11 
   log  'installer is installed'
  else
    log 'installer is not installed so procceding with the installation' 
 
