predict_proba returns different results on Python 2 & 3 I had some old code used to train a Random Forest Classifier (sklearn 0.17.1), for classification on two classes (spam/ham). I ran this in a docker container and sent it some data. 

Sklearns predict_proba returns [0.3, 0.7].

I “rewrote” (literally changed a few lines for Python3 compatibility), trained with the same data, and sent it the same data, and now predict_proba returns [0.7, 0.3]. 

Did something change in sklearn.ensemble.RandomForestClassifier predict_proba or have I messed up somewhere, or does the new one still work?
Maybe...
Have a you seen if one of the predict_proba produces 2 columns?

I think Python 3 produces two columns and the one comparable is the second.