In computer programming, a postcondition is a condition or predicate that must always be true just after the execution of some section of code or after an operation in a formal specification. Postconditions are sometimes tested using assertions within the code itself.

What is a postcondition Python?

A precondition is something that must be true at the start of a function in order for it to work correctly. A postcondition is something that the function guarantees is true when it finishes. An invariant is something that is always true at a particular point inside a piece of code.

What are the postconditions of a function?

A postcondition is a predicate that should hold upon exit from a function. It expresses the conditions that a function should ensure for the return value and/or the state of objects that may be used by the function.