I'm using a data frame like this:
home_team away_team  home_score  away_score 
Scotland   England           0           0   
England   Scotland           4           2   
Scotland   England           2           1   
England   Scotland           2           2   
Scotland   England           3           0   
Here's what I would like to accomplish, I'm trying to regroup all the country together whether they are home or away and have the sum total of the score.
Team    total goal
Scotland   9
England    7
 
     
    