code: def update_score(self, node, addToScore):
          
          current_score = 0
          score_string = self.parser.getAttribute(node, 'gravityScore')
          if score_string:
              current_score = int(score_string)
  
          new_score = current_score + addToScore
          self.parser.setAttribute(node, "gravityScore", str(new_score))
docs: \
          adds a score to the gravityScore Attribute we put on divs
          we'll get the current score then add the score
          we're passing in to the current