What Did You Call That?

• A function definition introduces a new variable that refers to a function object. The return statement describes the value that will be produced as a result of the function when this function is done being executed.

• A parameter is a variable that appears between the parentheses of a function header.

• A local variable is a variable that is used in a function definition to store an intermediate result in order to make code easier to write and read.

• A function call tells Python to execute a function.

• An argument is an expression that appears between the parentheses of a function call. The value that is produced when Python evaluates the expression is assigned to the corresponding parameter.

• If you made assumptions about the values of parameters or you know that your function won’t work with particular values, write a precondition to warn other programmers.