from disnake.ext import commands

bot = commands.Bot(...)
bot.load_extension('docs')

bot.run(...)

from disnake.ext import commands
from docs import cog


class MyCog(cog.Docs):
    def __init__(self, bot):
        super().__init__(bot)
        # Now we set the new items
        # NOTE: It must be a list of tuples or a tuples of tuples
        self.items = (
            ('disnake', 'https://disnake.readthedocs.io/en/latest/'),
            ('python', 'https://docs.python.org/3/'),
            ('aiohttp', 'https://aiohttp.readthedocs.io/en/stable/'),
        )
        # NOTE: You must also add `disnake` and `python` manually, otherwise
        # it will only show the items you put.


bot = commands.Bot(...)
bot.add_cog(MyCog(bot))

bot.run(...)