I tried to add a claim on Q22010361 (https://www.wikidata.org/wiki/Q22010361) to https://www.wikidata.org/wiki/Q21345747 , but turns out it was redirected.
```
pywikibot.data.api.APIError: modification-failed: [[Q21345747|Q21345747]] not found [messages:[{u'html': {u'*': u'<a href="/wiki/Q21345747" title="Q21345747" class="mw-redirect">Q21345747</a> not found'}, u'name': u'wikibase-validator-no-such-entity', u'parameters': [u'[[Q21345747|Q21345747]]']}]; help:See https://www.wikidata.org/w/api.php for API usage]
```
The error message is incorrect. The entity at https://www.wikidata.org/entity/Q21345747 exists, it's just a redirect. Correct behaviour would be either:
* Just accept it and add the target item (bit like how you get redirected when you open https://www.wikidata.org/entity/Q21345747)
* Throw an error that I'm trying to make a claim with a redirect as target (preferable with the Q id of the target so it's easy to recover)
I would of course prefer option 1.