Replacing The Value In New Data Frame Python

As you seen on the image we have three columns so i need to write code that can create new columns called aa and replace when whever see A replace it with 1 or B replace it 2 ETC.

Solution 1:

IIUC use:

df['aa'] = df['categories'].map(df.drop_duplicates('categories').set_index('categories')['WOF'])