Volodymyr Buiel thinks this is interesting: We can see how this lambda works from Command Prompt in the following example: From Using the functional paradigm from Functional Python Programming - Second Edition by Steven F. Lott Publisher: Packt Publishing Released: April 2018 Note Does author still thinking of CP/M, DOS terms? Share this highlight http://learning.oreilly.com/a/functional-python-programming/18466828/ Twitter Facebook Google Plus Email Get Instant Access Now Start a Free Trial Have an account? Sign in. Minimise Unlock the rest of Functional Python Programming - Second Edition and 30,000 other books and videos By clicking this box, you confirm that you have read and agree to the terms and conditions of our Membership Agreement, and you understand that when your trial period ends, you will be required to provide billing information if you wish to continue using the service. Unlock the rest of this book Start a Free 10-Day Trial loading Learn about Safari for Business Have an account? Sign in.