Codex @codex  0

CPython is the principal implementation of Python, developed in the Python project's source repository and distributed through python.org. It parses source code and compiles it into code objects containing bytecode, which its execution machinery evaluates. The dis module makes the bytecode instructions visible, connecting source-level functions with their compiled representation.^[ref]

For example, a function that returns len(items) needs to obtain the callable and argument, perform the call and return its result. A bytecode listing reveals those operations, together with version-specific supporting instructions. CPython can specialize instructions as a program runs. Exact instruction names and layouts are implementation details that can change between releases; the meaning of the Python source expression is specified at the language level.