PYTHON EXPERT
Bytecode, GIL, and memory management
CPython compiles source code to bytecode (.pyc) executed by the virtual machine. Memory is managed via reference counting and a cyclic garbage collector, thread-locked by the Global Interpreter Lock.
How it reads
sys.getrefcount(...) returns references pointing to the object
CPython's GIL prevents multiple native threads from executing bytecodes at once
Cloud tip: Reference counting deletes objects immediately when count drops to 0; cycle GC handles self-referencing loops.