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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_chat_description( self, chat_id: Union[int, str], description: str ) -> bool: """Use this method to change the description of a supergroup or a channel. You must be an administrator in the chat for this to work and must have the appropriate admin rights. Args: chat_id (``int`` | ``str``):
 Unique identifier (int) or username (str) of the target chat. description (``str``):
 New chat description, 0-255 characters. Returns: True on success. Raises: :class:`RPCError <pyrogram.RPCError>` in case of a Telegram RPC error. ``ValueError`` if a chat_id doesn't belong to a supergroup or a channel. """

        peer = self.resolve_peer(chat_id)

        if isinstance(peer, (types.InputPeerChannel, types.InputPeerChat)):
            self.send(
                functions.messages.EditChatAbout(
                    peer=peer,
                    about=description
                )
            )
        else:
            raise ValueError("The chat_id \"{}\" belongs to a user".format(chat_id))

        return True