The core principle governing this concept is the semantic definition of function return values as the transfer of computational state from a function's local scope to the caller's environment. Formally, a return value is defined by the expression's evaluation within the function body, where its type and identity are determined by the language's type system and object reference mechanisms. This mechanism operates within the subfield of imperative programming theory, specifically addressing data flow control, expression semantics, and the distinction between void operations and value-yielding functions.
Prerequisite chain context: requires Using AND, OR, and NOT in Python.