Anonymous functions with lambda

So far, we’ve used def to define functions. It can get a little silly when the functions are short, like our get_id and get_name examples. Python supports anonymous functions using the lambda keyword (borrowed from the lambda calculus). Here’s an example:

Notice that we don’t need to write a return here: when using lambda, you just write an expression, and that’s what is returned. If you find yourself writing a lambda that does a lot… then it’s time to break out def and write a fuller function. Lambda functions are best for short bits of code, like when calling map or filter or list.sort: