Speed up copy.deepcopy() of containers holding atomic elements

copy.deepcopy() copies a structure by sending every element back through deepcopy(). For elements that need no copying at all — strings, ints, None, booleans, floats and the other immutable atomic types — that round trip still costs a function call each, even though the value handed back is the same object.

Real data is dominated by these atomic leaves. A parsed JSON document, a settings dict cloned before mutation, a record copied inside a framework: the keys are strings and most values are strings and numbers. Copying such a structure spends most of its time calling deepcopy() only to receive the same object straight back.

Deep-copying 105 JSON documents drawn from the top-1000 PyPI projects takes 1.20 ms today. Folding the atomic-type check into the dict, list and tuple copiers brings that to 970 µs, 23% faster, with identical handling of shared references, recursive structures and int/tuple subclasses.

Linked PRs

• gh-150822

Bắt đầu từ điểm vào copy.deepcopy() và kiểm tra PR được liên kết gh-150822, cho biết công việc đã được tiến hành. Xác minh rằng tối ưu hóa được báo cáo vẫn giữ nguyên các tham chiếu dùng chung, cấu trúc đệ quy và cách xử lý lớp con của int/tuple, đồng thời đạt mức cải thiện benchmark đã nêu.