!doc for stdlib items gives 2to3 results

[lemonsaurus]

For some reason, calling !doc get dict or !doc get filter will fetch the docs from 2to3 rather than displaying the docs for the built-ins.

[jchristgit]

That is a thing I've spotted for a while but wasn't sure with how to fix it. I believe we should be able to add an exclusion list to the inventory fetching, but that will be very expensive due to the number of symbols involved. Relevant code snippet:

        fetch_func = functools.partial(intersphinx.fetch_inventory, config, '', inventory_url)
        for _, value in (await self.bot.loop.run_in_executor(None, fetch_func)).items():
            # Each value has a bunch of information in the form
            # `(package_name, version, relative_url, ???)`, and we only
            # need the relative documentation URL.
            for symbol, (_, _, relative_doc_url, _) in value.items():
                absolute_doc_url = base_url + relative_doc_url
                self.inventories[symbol] = absolute_doc_url