Why This Old Python Performance Trick Doesn’t Matter Anymore

CPython 3.11's instruction specialization has made the old Python optimization trick of creating local aliases for global functions largely obsolete. The specializing adaptive interpreter now automatically optimizes global lookups by caching builtin function indices and skipping unnecessary dictionary lookups, making LOAD_GLOBAL_BUILTIN nearly as fast as LOAD_FAST. However, the optimization still provides benefits for imported functions with qualified names like math.sin, where multiple lookup levels create overhead that local aliases can eliminate.