RK-A

I found an inconsistency in the way values are being stored in the has_noun function in two different places in BR3_IR3_tagger.py. In extract_single_uncommon_words, with the header as key, the list of (word, pos_tag) is saved as the value whereas, in the assign_subtract_const function, the value is stored as a list of pos_tags.

This is causing issues in the assignment of the correct subtract_const value for a header variant. We need to make sure that in the assign_subtract_const function as well, the values are stored as a list of (word, pos_tag) and subsequent changes are made to ensure that the functionality of assign_subtract_const is not affected.