how do I send files with an discord bot py - discord.py

Question

I m trying to send a file with my bot but if I search how to do this I alway get somthing I cant use because I m using
#client.tree.command and Interaction
and not #bot.command and ctx
I tried:
#client.tree.command()
async def download(interaction: discord.Interaction,link:str):
await interaction.response.defer(ephemeral=True)
link1 = link
yt = YouTube(link1)
yd = yt.streams.get_highest_resolution()
yd.download("C:\\Users\\phili\\OneDrive\\code\\discord bot")
await interaction.followup.send(file=f"{yd.title}.mp4")
I got:
Traceback (most recent call last):
File "C:\Program Files\Python311\Lib\site-packages\discord\app_commands\commands.py", line 862, in _do_call
return await self._callback(interaction, **params) # type: ignore
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\phili\OneDrive\code\discord bot\main.py", line 512, in download
await interaction.followup.send(file=f"{yd.title}.mp4")
File "C:\Program Files\Python311\Lib\site-packages\discord\webhook\async_.py", line 1706, in send
params = handle_message_parameters(
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python311\Lib\site-packages\discord\http.py", line 241, in handle_message_parameters
attachments_payload.append(attachment.to_dict())
^^^^^^^^^^^^^^^^^^
AttributeError: 'str' object has no attribute 'to_dict'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Program Files\Python311\Lib\site-packages\discord\app_commands\tree.py", line 1242, in _call
await command._invoke_with_namespace(interaction, namespace)
File "C:\Program Files\Python311\Lib\site-packages\discord\app_commands\commands.py", line 887, in _invoke_with_namespace
return await self._do_call(interaction, transformed_values)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python311\Lib\site-packages\discord\app_commands\commands.py", line 880, in _do_call
raise CommandInvokeError(self, e) from e

Answer 1

In discord.py, the file argument (for any Messageable) is expected to be an instance of the File class. So to send a locally saved file or downloaded file, you need to use the File class constructor.
file = discord.File("exact/path/to/the/file.mp4")
await interaction.followup.send(file=file)
Its first argument expects to be a path to the file or a file-like object.