AWS backup is not in the list of command line interface commands

When I'm trying to use aws backup on my AWS server through command-line interface, but it's not in the list of available commands. How do I add this in?

Currently when I run

aws backup

I get the following:

usage: aws [options] <command> <subcommand> [<subcommand> ...] [parameters]
To see help text, you can run:

  aws help
  aws <command> help
  aws <command> <subcommand> help
aws: error: argument command: Invalid choice, valid choices are:

acm                                      | apigateway                              
application-autoscaling                  | autoscaling                             
budgets                                  | cloudformation                          
cloudfront                               | cloudhsm                                
cloudsearch                              | cloudsearchdomain                       
cloudtrail                               | cloudwatch    

etc.

there's no backup in there.

How do I launch aws backup commands then?

Upgrade your aws-cli. More likely than not you’ve got an old version that doesn’t yet have backup support.

What’s your aws --version output?