Functions act as placeholders for the data they output. Basically, you can assign the output of a function to a variable, just like any normal data.The core concept of this lesson is to learn how to call a function and assign the return value to a variable. We can take the return value of a function and assign it to a variable. Assume we have pre-defined a function sum which adds two numbers together. FreeCodeCamp offers a curriculum and in this video we cover their lesson called Assignment with a Returned Value. Feedback Delivered Instantly. Return graded assignments with a single click (optional). Students who have not been enrolled in classes at UC San Diego for two or more consecutive quarters must request to return to the University.