code: def is_cellular_component(self, go_term):
          
          cc_root = "GO:0005575"
          if go_term == cc_root:
              return True
          ancestors = self.get_isa_closure(go_term)
          if cc_root in ancestors:
              return True
          else:
              return False
docs: Returns True is go_term has is_a, part_of ancestor of cellular component GO:0005575