How to use Python Lambda functions: a 5 minute tutorial

A lambda function is declared differently than a normal function. In Python, lambda functions have the following unique characteristics:

A lambda function in Python uses the following basic syntax. As we mentioned before, we use the lambda keyword to create a simple function in a Python expression.

A lambda expression can have any number of arguments (including none). For example:

In the following example, we use a lambda function to replace an area function:

The lambda keyword identifies the lambda expression. In the above example, x is the only parameter. The colon ends the parameter list and introduces the body of the function.

To use this expression properly, you place it wherever you might normally use a function object. This piece of code below creates a temporary, anonymous function object and passes it into the sorted function, which then performs the sort.