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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 get_chat_member( self, chat_id: Union[int, str], user_id: Union[int, str] ) -> "pyrogram.ChatMember": """Use this method to get information about one member of a chat. Args: chat_id (``int`` | ``str``):
 Unique identifier (int) or username (str) of the target chat. user_id (``int`` | ``str``):
: Unique identifier (int) or username (str) of the target chat. For your personal cloud (Saved Messages) you can simply use "me" or "self". For a contact that exists in your Telegram address book you can use his phone number (str). Returns: On success, a :obj:`ChatMember <pyrogram.ChatMember>` object is returned. Raises: :class:`RPCError <pyrogram.RPCError>` in case of a Telegram RPC error. """

        chat_id = self.resolve_peer(chat_id)
        user_id = self.resolve_peer(user_id)

        if isinstance(chat_id, types.InputPeerChat):
            full_chat = self.send(
                functions.messages.GetFullChat(
                    chat_id=chat_id.chat_id
                )
            )

            for member in pyrogram.ChatMembers._parse(self, full_chat).chat_members:
                if member.user.is_self:
                    return member
            else:
                raise UserNotParticipant
        elif isinstance(chat_id, types.InputPeerChannel):
            r = self.send(
                functions.channels.GetParticipant(
                    channel=chat_id,
                    user_id=user_id
                )
            )

            users = {i.id: i for i in r.users}

            return pyrogram.ChatMember._parse(self, r.participant, users)
        else:
            raise ValueError("The chat_id \"{}\" belongs to a user".format(chat_id))