docs: def _add_edge(self, s_a, s_b, **edge_labels):
          """
          Add an edge in the graph from `s_a` to statement `s_b`, where `s_a` and `s_b` are tuples of statements of the
          form (irsb_addr, stmt_idx).
          """
          # Is that edge already in the graph ?
          # If at least one is new, then we are not redoing the same path again
          if (s_a, s_b) not in self.graph.edges():
              self.graph.add_edge(s_a, s_b, **edge_labels)
              self._new = True
              l.info("New edge: %s --> %s", s_a, s_b)