new_contents: def get_block_device():
      '''
      Retrieve a list of disk devices
      '''
      cmd = '/bin/lsblk -n -io KNAME -d -e 1,7,11 -l'
      dev = __salt__['cmd.run'](cmd).splitlines()
      for i in dev:
          if i not in os.listdir('/dev'):
              raise CommandExecutionError(
                  'Invalid device found'
              )
      return out
  
subject: Create salt-custom.py