print(df)    Apples  Bananas  Grapes  Kiwis 0     2.0      3.0     NaN    1.0 1     1.0      3.0     7.0    NaN 2     NaN      NaN     2.0    3.0  df['Fruit Total']=df.iloc[:,-4:].sum(axis=1)  print(df)    Apples  Bananas  Grapes  Kiwis  Fruit Total 0     2.0      3.0     NaN    1.0          6.0 1     1.0      3.0     7.0    NaN         11.0 2     NaN      NaN     2.0    3.0          5.0

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