tokens: What I want to do , is for every row ( uniquely identified by docnr ) to take the date and the client id , and find all of the other rows that have the same clientid , and an earlier date .
ner_tags: O O O O O O O O O B-Data_Structure O O O O B-Variable O O O O B-Variable O O B-Variable I-Variable O O O O O O O B-Data_Structure O O O O B-Variable O O O O B-Variable O