code: def infer_category(self, id):
          
          logging.info("Attempting category inference on id={}".format(id))
          toks = id.split(":")
          idspace = toks[0]
          c = None
          if idspace == 'DOID':
              c='disease'
          if c is not None:
              logging.info("Inferred category: {} based on id={}".format(c, id))
          return c
docs: heuristic to infer a category from an id, e.g. DOID:nnn --> disease