how to create a new column from a row containing specific column name in brackets in pandas

Hello all I have a simple df as shown above. Target column contains column names created with a lambda from other table

targetmain['Target']=targetmain.apply(lambda row: row[row == 1].index.tolist() , axis=1)

What I want to do is to create a new column based on Target column named "Primary", checking what is the target and the number matching the respective column. (eg. for Joe the column "Primary" should be 5, jack 2,avarel 0, william 8)

also if the brackets are an issue I can remove them as well.

>Solution :

First remove lists by seelcting first value and then use lookup:

targetmain['Target'] = targetmain['Target'].str[0]

idx, cols = pd.factorize(targetmain['Target'])
df['Primary'] = targetmain.reindex(cols, axis=1).to_numpy()[np.arange(len(targetmain)), idx]

For old pandas versions use DataFrame.lookup:

targetmain['Target'] = targetmain['Target'].str[0]
targetmain['Primary'] = targetmain.lookup(targetmain.index, targetmain['Target'])