discordpy .fetch_message(804828125745774652) code example

Example 1: on message discord py

@bot.event
async def on_message(message):
    if message.content == "pong":
        await message.channel.send('ping')

Example 2: discord.py fetch channel

await client.fetch_channel(channelId)

Example 3: discord py fetch channel by id

channel = discord.utils.get(ctx.guild.channels, name=given_name)
channel_id = channel.id