Nunez was sent off on his Anfield debut against Crystal Palace a fortnight ago for headbutting Eagles defender Joachim Andersen.
Liverpool survived Nunez's dismissal in that game to draw 1-1 but he missed subsequent matches against Manchester United, Bournemouth and Newcastle United.
Liverpool lost to the Red Devils but picked maximum points against the Cherries and Eddie Howe's side, with Roberto Firmino leading the lining superbly in Nunez's absence with three goals and as many assists.
Having completed his suspension, Nunez is back in the fold for Saturday's Merseyside Derby against Everton, and Klopp believes there will not be a repeat of such histrionics from the 23-year-old.
"He learned a lesson! He's in really good shape," Klopp said ahead of the game.
"If you look how we came through the last two games, winning, we don't see it as a bad thing. We tried to give him extra input physically as well as tactically.
"Diogo will probably be in as well for the first time, so it'll be the first time with five attackers, it's like Christmas. We will make changes, we will see.
"He's really happy that he's not suspended. For some time always I've given him a high five but a slap as well, just so he doesn't forget! That can stop now.
"He's looking forward to it. His English didn’t improve much in 10, 15 days, so I don't know exactly, but it looks like it."
Nunez has one goal and one assist from his two Premier League games so far.
