Добавьте два значения столбцов Datframe в один
df["period"] = df["Year"] + df["quarter"]
Tremendous Enceladus
df["period"] = df["Year"] + df["quarter"]df = df['Day'].map(str) + '-' + df['Month'].map(str) + '-' + df['Year'].map(str)
df1 = df['1st Column Name'].map(str) + df['2nd Column Name'].map(str) + ...
df['Fruit Total']= df.iloc[:, -4:-1].sum(axis=1)
print (df)
Apples Bananas Grapes Kiwis Fruit Total
0 2.0 3.0 NaN 1.0 5.0
1 1.0 3.0 7.0 NaN 11.0
2 NaN NaN 2.0 3.0 2.0