Traceback (most recent call last):


 "ponyfail_077.py", line 33, in <module>

Post.select().prefetch(Post.tags, PostTag.tag, Tag.category).first()


 "lib/python3.4/site-packages/pony/orm/core.py", line 5888, in first

objects = query.without_distinct()[:1]


 "lib/python3.4/site-packages/pony/orm/core.py", line 6131, in __getitem__

return query._fetch(limit=stop-start, offset=start)


 "lib/python3.4/site-packages/pony/orm/core.py", line 6133, in _fetch

return QueryResult(query, limit, offset, lazy=lazy)


 "lib/python3.4/site-packages/pony/orm/core.py", line 6240, in __init__

self._items = None if lazy else self._query._actual_fetch(limit, offset)


 "lib/python3.4/site-packages/pony/orm/core.py", line 5794, in _actual_fetch

if query._prefetch: query._do_prefetch(items)


 "lib/python3.4/site-packages/pony/orm/core.py", line 5861, in _do_prefetch

objects_to_prefetch_dict[obj.__class__._root_].add(obj)
AttributeError: type object 'NoneType' has no attribute '_root_'

Traceback (most recent call last):


 "/usr/local/lib/python3.6/dist-packages/discord/ext/commands/core.py", line 62, in wrapped

ret = yield from coro(*args, **kwargs)


 "/usr/local/lib/python3.6/dist-packages/redbot/cogs/audio/audio.py", line 1428, in skip

return await self._skip_action(ctx)


 "/usr/local/lib/python3.6/dist-packages/redbot/cogs/audio/audio.py", line 1492, in _skip_action

pos, dur = player.position, player.current.length
AttributeError: 'NoneType' object has no attribute 'length'
