Reproduce: python harvest_template.py -lang:en -template:"Sockpuppet" -namespace:2 -create 1 P370 (This is only an example to reproduce the bug; no new items will be created as they will be stopped by abusefilter)
Result: When creation of an item is failed wikidata:-1 will returned; the bot will try to add statements to wikidata:-1 and pywikibot.exceptions.OtherPageSaveError will be throwed which make the bot crash
Expected: If an item can not be created due to network error or rate limit, retry creation after some time. Otherwise (e.g. stopped by abusefilter), skip the current page and proceed the next one.