Deletting all messages sent by my bot into a chat.

[alebuffoli]

Hello.
I'm trying hard to delete all the messages sent by my bot into a chat.
I know that it is not possible to delete the messages sent by the user, so, i want at least delete all the messages sent by my bot.

so far to save a message id sent from my bot I use this code

messages_ids.update({chat_id: lastMessage})

That store in a dictionary the chat ID and all the information about the last messages that the bot sent.

Then, I delete the last message whit this method:

bot.deleteMessage(telepot.message_identifier(messages_ids[chat_id]))

But obviously I can't delete the message sent to a user before I implemented this method.
So, to clear the old chats, can I delete in someway all the message sent by my bot?

Or maybe there is a way to get all the messages ids of messages already sent? In this way I'd do a for cycle.
But I cannot do a for cycle without the ids because I should check hundred thousand messages for chat and obviously it would be really slow and annoying.

Hopefully there is an easier solution, Thankyou.