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Changes between Initial Version and Version 1 of Ticket #13394, comment 24

initial	v1
1	1	With the latest commit, there is a context manager preventing the dictionary from negative effects of deletions. The doctests show what the context manager is capable of.
2	2
3		It is still "needs review". Perhaps one should test if the whole thing is still faster than `weakref.WeakValueDictionar~~`. Even if it is (more or less) equally fast, it is a progress, since `sage.misc.weak_dict.WeakValueDictionary` now seems to be bullet proof regarding garbage collection and explicit deletions~~.
	3	It is still "needs review". Perhaps one should test if the whole thing is still faster than `weakref.WeakValueDictionary`. Since `sage.misc.weak_dict.WeakValueDictionary` now seems to be bullet proof regarding garbage collection and explicit deletions, we should use it, unless it is significantly slower than Python's own implementation.
4	4
5	5	Challange: Try to break it...