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apply dataframe pandas python

Add 2 new columns to existing dataframe using apply

I want to use the apply function that:
– Takes 2 columns as inputs – Outputs two new columns based on a function.

An example is with this add_multiply function.

#function with 2 column inputs and 2 outputs
def add_multiply (a,b):
return (a+b, a*b )
#example dataframe
df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
#this doesn't work
df[['add', 'multiply']] = df.apply(lambda x: add_multiply(x['col1'], x['col2']), axis=1)

ideal result:

col1  col2  add  multiply
1 3 4 3
2 4 6 8