I want to create a new variable with include all drugs DS59 - DS71 (values currently coded: 1 = never used, 2 = rarely use, 3 = occasionally use, and 4 = regularly use). I want one of three classes to be assigned to each subject as laid out below:

1. no user: no use on any of the drugs (all 1's)
2. experimenter/light user: low overall score on drug use across all classes (total summed score less than 20) and no "regularly use (4)" answers to any drug classes
3. regular user - high overall score on drug use across all classes (score above 20) and at least one "occasionally use (3)" or "regularly use (4)" answer to any drug class

This is my current code - I am unsure how to most appropriately write the conditionals.

druglist=[(df['DS59']),(df['DS60']),(df['DS61']),(df['DS62']),(df['DS63']), (df['DS64']),(df['DS65']),(df['DS66']),(df['DS67']),(df['DS68']), (df['DS69']),(df['DS70']),(df['DS71'])] conditions=[ (druglist== ), (druglist==), (druglist== )] values=['no user','experimenter/light user','regular user'] df['drugs']=np.select(conditions,values)