Bytecode and .pyc files

on YouTube ↗32m

" summary

Deep dive into CPython bytecode and .pyc internals: how co_code, co_consts and co_varnames map to evaluation stack operations and instructions like LOAD_CONST, LOAD_GLOBAL, CALL_FUNCTION and BINARY_OP; how .pyc headers store a magic number and timestamp (or hashed variant) and why __pycache__ names include the Python version; tools shown include dis and dis.get_instructions, marshal for reading code objects, and creating functions with FunctionType and code.replace to patch one byte and change an operator — the edit works and executes.

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" chapters (13)

1. 0:00Introduction
2. 1:11What is bytecode
3. 3:22Bytecode vs machine code
4. 4:31Inspecting bytecode
5. 8:24Stacks in execution
6. 17:27Why .pyc files matter
7. 19:58Optimizing with .pyc files
8. 21:03Inside .pyc files
9. 22:51Bytecode optimization levels
10. 23:34Exception handling in bytecode
11. 24:18Dynamic function creation
12. 28:15Practical bytecode tricks
13. 29:51Q&A

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