This occurs when handling a recursion error uses more than 50 extra nested function calls:

if (tstate->overflowed) {
        if (tstate->recursion_depth > recursion_limit + 50) {
            /* Overflowing while handling an overflow. Give up. */
            Py_FatalError("Cannot recover from stack overflow.");
        }
        return 0;
    }



You can set the recursion limit with sys.setrecursionlimit(), but it is the extra stack depth that matters here.