Suma grupy i średnia 2 kolumny
d = {'Missed':'Sum1', 'Credit':'Sum2','Grade':'Average'}
df=df.groupby('Name').agg({'Missed':'sum', 'Credit':'sum','Grade':'mean'}).rename(columns=d)
print (df)
Sum1 Sum2 Average
Name
A 2 4 11
B 3 5 15
Drab Dog