Lambda functions (also called anonymous functions) are tiny functions that have no name and only have one expression as their body.
In Python they are defined using the
lambda <arguments> : <expression>
The body must be a single expression. Expression, not a statement.
This difference is important. An expression returns a value, a statement does not.
The simplest example of a lambda function is a function that doubles that value of a number:
lambda num : num * 2
Lambda functions can accept more arguments:
lambda a, b : a * b
Lambda functions cannot be invoked directly, but you can assign them to variables:
multiply = lambda a, b : a * b print(multiply(2, 2)) # 4
The utility of lambda functions comes when combined with other Python functionality, for example in combination with