Please help with an example of sending a photo to an arbitrary chat. Here's what I found myself

client.MessagesSendMedia(&telegram.MessagesSendMediaParams{
	Silent:       false,
	Background:   false,
	ClearDraft:   false,
	Peer:         &telegram.InputPeerUser{ // user data
		UserId:     2121212,
		AccessHash: 212121211221,
	},
	ReplyToMsgId: 0,
	Media:        ???, 
	Message:    

In the TDLIB update event, there is only the 'sender_user_id' field and no other user identification. Currently, there is no way to get first and last names using python-telegram.
As far as I know, to get that information the client should use getUserFullInfo() method. Please, add it.