some legacy corpora don't have filled out the left/right_token column
some legacy corpora don't have filled out the left/right_token column

amir-zeldes/ANNIS,korpling/ANNIS,amir-zeldes/ANNIS,amir-zeldes/ANNIS,zangsir/ANNIS,zangsir/ANNIS,korpling/ANNIS,korpling/ANNIS,zangsir/ANNIS,amir-zeldes/ANNIS,korpling/ANNIS,zangsir/ANNIS,zangsir/ANNIS,korpling/ANNIS,amir-zeldes/ANNIS,amir-zeldes/ANNIS,zangsir/ANNIS